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Here is some shop tips we hope you find helpful. Helpful Hints – from Lapidary Shop Manual – Edited by Elmer Yoder – Compiled in Electronic Form and Re-Edited By Cameron Speedie Please Note - due to concerns of Copyright infringement all notes from the Canadian Rockhound have been removed. This is to alleviate any concerns the current editor of the Canadian Rockhound may have regarding crediting specific Authors, date of publication, page number, volume, issue etc. As the only source of information I have is an old shop manual and it does not provide the information that the Canadian Rockhound Editor requires, the only option was to remove the articles. I will endeavor to provide suitable articles of comparable information. Please feel free to distribute but acknowledge the sources - Thanks. There will be more coming and I will index it once it is complete. There is about 60 pages and the original is very poor quality so the ol' OCR (optical character recognition - computer looks at a page and translates it to text) is quite challenged so the human OCR has a lot to do! If you want to contribute feel free to email us - we might even send you a freebie! Old Miner’s Rule While a miner’s tools, equipment and personal belongings remain in or next to a digging, that is his until he relinquishes it either by removing said property or announcing that he is finished digging in that area. Furthermore, specimens or rocks cached on or near said personal property are also the property of the miner and shall not be touched or removed without his express permission. Every Rockhound should obey this rule. Via the Geode Abalone (Editor’s note – due to the near extinction of the species the harvesting of Abalone in Canada is prohibited – please use only old shells or from foreign sources) Abalone, (Haliotis), for over 80 million years, has been grazing on algae in the selected waters of our planet earth. Eight species may be found along the West Coast of the North American continent, from Mexico to the Aleutian Islands. They are: Red Black, Corrugated, Green, Flate, White, Pinto, and Threaded. These shells are comprised of multi-layered "Mother of Pearl" nacre, chemically similar to the Oyster. Colour bands found in the shells are a direct result of diet and genetic factors. The outer layer is protected by a covering called Peristrum, which is a transluscent shellac-like overlay. These beautiful shells have been found all over the world in many forms. In ancient times, royalty decorated their robes and turbans with them, Stings of Abalone shell jewelry were used by the women. During the era of barter and trade, the Abalone was often used as "coin of the realm". In many parts of the world, at archeological digs, artifacts have been found made from these shells. Today, many forms of jewelry, from formal to baroque, are designed with the unique characteristics and beauty of the Abalone utilized to the fullest. Many steps are used in the preparation of the shell until its final lustrous beauty is brought to life in the creation of fine jewelry. Working with Abalone (Editor’s note – Abalone is extremely toxic if worked dry. Do not ever work this material unless the piece is under a steady stream of water. If you feel the least bit nauseous even when working it wet – stop immediately and get plenty of fresh air. ) Starting with the raw shell, it must first be soaked in a chemical to rid it of algae and parasitic crustations. It is scrubbed, dried, sandblasted, before it is ready for cutting. Rough shapes are formed by saw, drill, and dremel tools using diamond edged tools. This work should be done under water, with a worker wearing a respirators, plus fans blowing for ventilation to protect the workers from Silicosis, due to the dust of Calcium Carbonate from the shells. After the cutting operations are completed, the shell parts can be placed in a tumbler for 24 to 72 hours with three changes of grit. The shell is then washed, and buffed to a high gloss finish. This last operation can be done either mechanically or by hand. The shell should now be a beautiful creation of vivid colour worthy of any jewelry setting. All that is left now is the imagination of the craftsman. The shell can be drilled for jump rings, epoxied for any glued style, or prong set for special effects. Completion of any of these operations assures the individual of the finest in Abalone jewelry. The world’s population has for years, gorged itself on these delectable Gastropods (Editor’s note – if you enjoy fish flavored shoe leather ; ) ), thus over-harvesting their reproductive capacity. The Sea Otter also includes Abalone as a main part of his diet, and that also reduces the reproduction. Our federal government has stepped in and placed an "Endangered Species" label on the Abalone for these reasons. Quantity limits as well as size limits have been placed on the harvesting of them. Thus, the Abalone has become more valuable, both as a food source and a jewelry source. From the Ultralite Co. Inc. via Chips and Tips Amber - re-constituted 'Ambroid" was the tern used by the Europeans for amber that was pressed or reconstructed by f'using small pieces of amber with the use of heat and pressure. The process was quite simple. Pieces were scraped and cleaned to remove dirt and weathered areas and impurities. The amber was then placed in a deep steel tray with a perforated partition. The container and the amber pieces were then subjected to heat to about 200 to 250 degrees centigrade. The tray was, also subjected to an hydraulic pressure of about 50,000 pounds per square inch. This forces the melted mass through the perforated partition and thereby mixes it and also forces it into molds where it cools and solidifies. Amber will melt at a temperature of 170 – 190 degrees centigrade, and then exhibits a rubber-like consistency without disintegrating so it should be possible to melt and press a mixture of amber chips without destroying the amber. Amber will burn so be careful if you attempt this! Early pressed amber had one major drawback - it became cloudy with age. Ambroid does however have an advantage as it is harder than natural amber. Working amber Amber can be worked very easily. It can be filed to shape and then sanded with an aluminum oxide paper of finer and finer grades, (200,400, and 600 grit) until a polish step is necessary. Amber can be polished by the use of: (1) tripoli with oil; (2) aluminum oxide; (3) tin oxide;(4) Linde A; (5) rouge, applied dry. Dip the amber piece into the lubricant (oil or water) and then dip the piece: into the polishing compound then rub vigorously on a smooth surface such as a leather strop, or a chamois attached to a hard board. The people in Europe and Mexico used wood ashes as a. polishing agent. Faceting Amber can also be faceted if the lap speed is reduced. Suggested cut-ting angles are: Cutting angles Cutting lap Cutting speed Culet - 43 degrees Fine - extra fine 100 RPM Crown - 42 degrees Polishing Lap - wax speed - normal agent - Linde A Polybern - Amber in plastic Amber can also be embedded into plastics or resins to make beads or ornaments. Commercial plastic resins are available - simply follow their casting procedures. from Coalmont / Blakeburn via The Geode Jade Lapidaries and jewelers should constantly attempt to call gemstones and rough material by their correct name. Jade has many other stones named after it, as any material. The confusion as to what jade is, has been compounded by this deceptive practice. Amazon jade is adventurine.. American jade is a rock - a mixture of idocrase and grossular. Australian jade is chrysophrase. Colorado jade is green microcline. Flukien, Manchurian, and Honan jade are all soapstone. Indian jade is adventurine. Jadite is pure jade. (editor’s note ? – not sure what he means) Jasper jade is green jasper. Korean jade is bowenite, a hard variety of serpentine. (Mexican jade is green dyed marble or calcite. Oregon jade is a dark green jasper. Silver Peak jade is malachite. Transvall jade is a massive variety of green grossular garnet. Real jade such as BC jade, Alaska or Yukon jade are truly nephrite jade: Nephrite Hardness 6-61/2 S.G. 2.95 R.I. 1.6 -1.63 Jadeite Hardness 61/2-7 S.G. 3.3 R.I. 1.66 - 1.68
Possibly more information (some true, some false) has been written regarding the polishing of jade than all other lapidary materials combined. And so, one concludes that jade is difficult to polish. The answer is "Yes" and "no". Let us consider the mineral itself. There are three separate and distinct minerals that are known under the general term jade: Nephrite, Jadeite, and Chloromelanite. Nephrite is the one found in BC, Alaska, and Wyoming. This is the one we shall consider here. Let us first consider the nature of these rock-forming minerals. They are described as being fibrous, which simply means that structurally, they are a mass or network of tiny fibrous hair-like crystals, much like straws in a straw stack. They are so fine in nephrite that they cannot be seen even with a powerful magnifier. A peculiarity about crystals is that they are generally softer parallel to the crystal growth, and harder across the crystal. It is just this simple characteristic that creates all the difficulty in applying a polish, if one uses the same procedure as for example, agate. However, provided one has the proper equipment and uses it in the proper manner, nephrite jade is easy to polish. And now for the job! Proper sanding is of vital importance. Improper sanding mainly through use of unsuitable equipment and technique, is the greatest cause of difficulty. We will assume that you have your cab ground to shape, and coarse-sanded on a disc or drum, using 120 or 220 grit. The 220 is slower, but otherwise it matters little which is used. Recommended sanding speed is about 1000 RPM for a ten-inch disc. And not too much pressure, for more reasons than one. We have all read of using a well worn sanding cloth for the final touches. This is O.K. for quartz minerals, but in my experience does not apply for jade, nor any other fibrous material. Crystalline Rhodonite, for example. It is obvious that sanding will tend to wear away the fibres parallel to the direction of rotation of the sander at a faster rate than the fibres at right angles. This pesky behavior is called undercutting, and must be avoided. If we use the well worn technique, we will probably decide that the old cloth isn't doing much,.. so a little extra pressure is added. What happens? In the first place, the stone is liable to be burned, creating nasty white spots, which, of course, must then be ground out. And that cab looks a little on the thin side already: But what is just as bad, if not worse, the sander (which has a small amount of resiliency) will be forced to plow out the parallel fibres and leave the cross-fibres already mentioned. What do we have now? Just plain orange peel. The obvious remedy is to use a sharp sander. No matter what number grit we are using. This will have a planing action which will remove material without undue pressure. After our cab has achieved a fine satin-like appearance all over, we may proceed to the fine sanding operation. But first, scrub the stone and dop stick to remove all traces of coarse grit. And make sure there is no grit (let's call it dust) anywhere- near the fine sander. 320 grit will be found quite satisfactory (and fine enough) for the final sanding. But here again, it must be new, sharp grit. Do not depend on this 320 to remove much material. As stated before, have a nice satin finish before leaving the coarse sander. The 520 grit will soon produce a mirror-like surface that 'night easily pass for a polish. Any areas that appear to have a "frosty" look are not sanded enough, and this frost must be removed. Actually, They are areas of small pits and depressions that are filled with sanding debris. We now have a semi-polished stone. This must again be very thoroughly scrubbed, particularly behind the stone where the dopping wax is located. And doubly important, this time, all dust must be removed from anywhere near the polisher. For polishing jade, we find that heavy harness leather, at least an eighth inch Thick is most suitable. Do not try to use light leather. A piece of felt floor covering makes a good cushion behind the leather. Chrome oxide is the most satisfactory polishing agent. Slow speed, not Over 350 RPM for a ten-inch disc works best. Quite' heavy pressure is generally required. Particularly for flat surfaces. And just enough water to keep the leather moist, applied with the chrome oxide in the form of a thin cream. Considerable pull will be felt as the leather dries cut. It is only while this pull or drag is felt, that actual polishing takes place. via The Laphound News Identifying jade 1. If you chip the edge of a suspected specimen and it sparkles or glitters, it's not jade. 2. If you can scratch it with a knife blade, it's not jade. 3.It should be much heavier than a common rock of similar size. 4.Tap The specimen lightly with the point of your pick. If a small moon-shaped fracture shows up, it is agate or jasper, but not jade. If it is jade, it will have a smooth, waxy, almost greasy, look and feel.
The Puget Sounder via The Rock Licker Carving Fire Agate The most important thing to remember before you even start is to select a good piece to work with. Carving is a very demanding aspect of the lapidary field. It requires patience, patience, patience. It is a time consuming venture into the unknown. You do not want to waste days or weeks working on an inferior piece of material. True, There is a chance you may destroy a beautiful layer of fire, but if this happens then go deeper and you may uncover another layer that is just as sensational. Keep this in mind and don't be afraid to dive in. The first step is to remove the layer of chalcedony that usually adorns the top of the fire layer. Remove this carefully. If the layer is thick you may wish to use a trim saw to partially remove some of the excess. Be very careful about trying to remove too much in This manner as you may be removing some fire also. I always leave some chalcedony - for two reasons. Number one is because you may wish to incorporate a portion of the chalcedony in the design. Number two is that the fire agate is botryoidal and part of the fire "bubbles" could extend up into the chalcedony. After removing as much as possible or advisable, be sure to clean the stone thoroughly. Just as in any other cutting process, all oil or coolant should be removed. The next step is to go to the hand tools. I use a Foredom Flex Shaft with a flexible handpiece #8AD. There are several very good motors and handpieces on the market, but in this article I am giving you the machines, tools and equipment that I work with. Always keep in mind that I am not endorsing any particular product. Before starting the actual grinding with your handpiece, you must have bowl or container of water beside your workspace. The stone must be worked wet at all times. I like a lot of extra work but my bowl is low and I use a block of styrofoam approximately 5"x5"x3" high as a support and steadying device. By resting my hands at the "heel" area above the wrist (on the block) it is a very simple matter to swing my hand over to the bowl of water and back to the business of grinding. This is my way of doing it, anything that feels right for you is the way to go. Just keep that stone wet. You must get down to the brown material which encompasses the fire layers. This is accomplished by using a heavy duty diamond sintered wheel. My preference is a 1/2" wheel. Through experience I have found the sintered wheels do an excellent job and do not have to be replaced as other types. I would also like to note at this point another reason I use diamond sintered wheels is because they work much faster than the silicon carbide or aluminum oxide points. As a beginner you can use the above mentioned points and turn out a beautifully finished product, it will just take longer. If you see that carving is for you, something you really enjoy doing, invest in the diamond points. It is an excellent investment. You do not need a wide variety of points to begin with. I started with a 1/2" heavy duty wheel; 1 diamond thin disc; 2 tapered cylinders - round head (1 small, 1 larger); 1 cone; 1 barrel; 2 flames (1 small, 1 larger). Your inventory can be added to as you progress, but the above will give you a good start. Once you get to the brown material, remove the heavy duty wheel and insert a barrel point in your handpiece. The barrel point is a versatile point - it clears larger areas in a hurry, but can be used to perform other jobs also. At this point let me suggest you take just any piece of agate and experiment with the various points and wheels. This way you can familiarize yourself with each one and learn its capabilities. Never force your points - use an easy stroke let the point or wheel do the work. This is where the fun begins You have now reached the first real stage of wonderful things to come. You should be able to see the contour of the fire lines. Study the piece carefully and try to see what the stone contains. It will tell you what you are going to carve from it. There is something waiting to be born and you can give it life. Take a fine- tipped felt point pen or an aluminum point or whatever you use to outline a cabochon and outline what you see. In other words, make a drawing on the stone of what you are going to carve. When you have outlined all of the main features, study it again. If there are any corrections to be made, now is the time to do it. Using your thin disc or separating disc, follow your "drawing" lines. You will be cutting into the stone, so keep that stone wet. As you cut these initial grooves you will find it easy to keep your cutting area wet as the water will follow the groove. It may be necessary to go back over This cutting procedure again in order to get the grooves as deep as you want them. it is better to cut thin grooves to start with. Remember, you have a great deal of grinding and sanding to do to actually shape your carving, so allow for this. Once the initial outline had been cut, you can go on to the business of rounding or detailing your carving. If you recall, I suggested earlier you take a rough piece of agate, of any kind, and practice using each point to familiarize yourself with its capabilities. You now want to make your carving as three-dimensional as possible, giving it a life-like appearance. This will not happen overnight. You will have to work and rework areas until you have achieved the right look for your particular piece. Use caution at all times. You do not want to grind or sand too close to the fire or you will end up erasing the fire. Fire layers are so thin that they will just disappear before your eyes, so leave enough of the brown layer above the fire to allow for the six to seven polishing stages you will be using. Work your carving with your various points until you achieve a fairly smooth surface. Now you are ready for The polishing stage. I use diamond compound in a syringe dispenser, usually 2 grams each, with mesh equivalent of 325; 600; 1,200; 14,000 and 50,000. Diamond compound will go a long way if used properly. I mix a small amount of compound, about the site of a wooden match head, with one drop of crystalube and make a paste of this. I then take a round toothpick and apply this pasta over the surface of the carving. Before going any further, let me explain the typo of point I use in my flex tool to achieve a brilliant polish. I turn my own wooden points, in various sizes. They are turned to fit the collet of my handpiece. I go to the lumber yard and buy a 3 foot length of 1/4" doweling (the hardest wood available), then cut it into 2 inch lengths, One inch for the shaft and one inch for the point. The shaft is turned to 1/8 inch diameter, the point being + inch (or less) at the base and shaped to a rounded point or cone shaped point. I also use the rounded toothpicks for areas the larger points can't reach. Wooden points are marvelous tools for polishing. They absorb the diamond compound and do not heat the stone as other agents do. Contamination is one thing that is to be avoided when using diamond compound. Just a minute grain of a courser compound can cause scratches on the surfaces that are not readily visible until you reach the final polishing stage. It may well be necessary for you to go back and start from scratch, which is something you want to avoid. After each stage of polishing, your carving must be completely cleaned of all the compound just used. This is the sane precaution you used when tumbling stones, and for the same reason. Start the polishing process with the 325 mesh and proceed with each of the next five mesh compounds following the above instruction. Remember, a fresh point must be used with each grade of compound. in order to avoid confusion on which point I had used for which compound, I marked the shaft with a #1 through #6 and stored my used points by sticking the shaft end into a large block of styrofoam, point up. This insures that they do not rub together or contaminate each other. The polishing process must not be hurried. Take plenty of time with each compound In order to insure a good polish. There are times when I am not completely satisfied with the final polish, so to give it a higher luster I will go to a cerium oxide or tin oxide. I soak the wooden point for a few seconds before applying the oxide. Remember, your stone will heat rapidly with oxides, so keep the stone wet during this operation. If you overheat the stone it will "scorch" the surface and you really have a problem. There again caution and patience apply. After reading these two articles you may think "it's not worth it". I have purposely stressed caution and patience because I want you to achieve good results on your first effort. Believe. me, it will all become "second nature" after a few experiments and will become an exciting and rewarding experience. It's like riding a bicycle, once you have learned, it becomes automatic. The joy or seeing a carving come to life far outweighs the time and effort put into a piece. By Lou Thorpe -- via Ore-Bits *****NEW Info - 12/20/98 - following section******** Opal Opal is a form of silica, chemically similar to quartz, but containing water within the mineral structure. Precious opal generally contains from 6 to 10 percent water and consists of small silica spheres arranged in a regular pattern. Opal occurs in many varieties, two of which are precious opal and potch. Color in precious opal is caused by the regular array of silica spheres diffracting white light, and breaking it up into the colors of the spectrum. The diameter and spacing of the spheres controls the color range of an opal. Opal colors also depends on the angle of light incidence, and can change or disappear when the gem is rotated. In potch opal, the silica spheres may be absent, or too small or irregularly arranged to produce color. The Opal Factory (Coober Pedy) Australia via Perfect Partners (Ketchikan Alaska) Varieties of Opal Many commonplace names have been given to varieties of opal generally referring to variations in color, structure, or some other characteristic of the material. The terms more general in usage today having a more specific reference to the material are gives here. Precious Opal - Exhibits a play of brilliant colors such as red, blue, orange, green, appearing as flashes, wavy or flame-like bands, and usually found in a translucent to nearly transparent matrix of a milky white or other body color. Black Opal- Has either a black or other very dark body color with a play of color. Harlequin Opal- has a variegated appearance in a mosaic-like pattern of color that is regular in shape and equal size. Pin-Fire Opal- Shows closely spaced pin points or specks of color. Matrix Opal- Is the term generally used to describe matrix material containing closely spaced veinlets or specks of opal and is sometimes used for cabochons. Fire Opal- Mainly from Mexico, is a type of precious opal having a body color that is relatively transparent, varying from pale yellowish to yellowish-red, orange to brownish-red, with a color play that is predominately red or orange, sometimes green. This name is improperly extended to the transparent or highly translucent opals having a red to orange-red or brownish-red that do not have color play. Girasol Opal- This name is of fairly recent origin and comes from the Italian words, Gira-re and Sole, meaning "to turn", and "the sun". It now refers to precious opal with a bluish or reddish color play, usually in a milky-white body color. Common Opal- In general this refers to opal without a play of color, also to opal without any degree of translucency, marking or body color, to make it valuable as an ornamental stone. Includes is this variety are milk opal, hyalite and opaque to semi-transparent opal of various ordinary color. Hyalite- Gets its name from the Greek word meaning glass. It often is found as a surface crust of other material in botryoidal, globular or kidney-shape forms. It can be colorless and clear as glass, or faintly colored with blue, green or greenish yellow, yellowish tones blending into a translucent or white material. Hydrophane- Is a white or light colored translucent to opaque type of opal that becomes almost transparent when placed in water. Cachalong - An opaque, white to yellowish colored type of opal with luster resembling mother of pearl. It is rather porous but does not become transparent in water. Milk Opal - Common opal of a translucent to opaque type being milk white, a pale bluish white or a greenish white in color. Wood Opal - Found as the petrifying material of wood. Often preserving the details of the wood structure and generally a yellowish or brownish color, but sometimes is a dark brown or brownish-black. Moss Opal - Contains dendritic or other imitative inclusions, similar in color, origin and appearance to those found in moss agates. via Michigan Gem News via Country Prospector How To Cut Triplets After you have removed as much excess matrix as possible with a hammer, trim the remaining matrix away with a saw. If oil is used in sawing, be sure to clean your opal with alcohol or acetone. The opal lies in bands or layers. Some nodules may have more than one band of fire so you must decide how you can get the most out of the piece you are working. If the bands are to close together to split with a fine saw blade, you will have to choose the brightest and most promising one. After you decide which band to work, saw parallel to the band. It is difficult at first to saw exactly parallel to the band, so don't try to saw right next to it. Leave approximately one-quarter of an inch matrix between where you saw and the layer of fire. Using a 180 grit diamond ripple disc, begin lapping away the excess material from the fire band. Be careful to lap parallel to the fire band. Lap down until the fire begins to show. Make sure plenty of water is used during the lapping process to keep the opal cool. When the fire begins to show, move to a 600 fine diamond lap and continue lapping until you are about half way into the layer of fire. Dry the opal and clean it with alcohol. Next apply a coat of fracture sealer to the opal and leave it set under a lamp or is the oven at 150 degrees for 20 to 30 minutes. Allow the stone to cool and wipe off the fracture sealer with a clean rag. Do not clean the fracture sealer off with acetone or alcohol. Now you are ready to glue the backing material on the opal. We have found that the best backing material is basalt or basanite. It is good and solid and less expensive then most other materials. We do not recommend obsidian as it is too brittle and is also too transparent when cut thin. Mix the glue according to the manufacturer's directions. We like the Epoxy 330. Make sure the kind you use is a crystal clear type. If using a two-part epoxy, roll the two parts together slowly. If you mix it fast air bubbles will develop. Make sure the backing material has been cleaned with acetone or alcohol if it has been sawed in oil. Coat the opal with epoxy. If you hold it under a light and tip it, you will be able to see any areas you may have missed. Place the Opal on the backing and press down firmly. This will push any air bubbles out from under the opal. After the glue has dried, saw parallel to the backing material allowing approximately one-quarter of an inch again between the backing and saw blade. After some practice, you will be able to saw closer than this. Lap the excess opal away using the ripple disc until the fire begins to show. Then finish lapping on the 600 fine disc. Lap as thin as possible. The opal should only be as thick as about two pieces of newspaper. Make sure the start is dry and clean. Apply another coat of fracture sealer and heat as before. Allow to cool and wipe sealer off with a clean rag. At this time you will decide where to place the quartz cap. If you are using the pre-cut kind. It is up to you now to decide what kind of stones you want. Some people like to make as big a stone as possible regardless of fractures, and others would rather make many small, but perfect stones. Of course, perfect stones have the highest value. When you have decided where to place the caps, mix the glue and coat the start with it. Again you can see any areas you may have missed by holding it up to the light and tipping it. Drop the caps straight down onto the start and press down firmly. It there are any air bubbles under the cap, they will look like bright silver spots. If air bubbles are present, remove the cap, apply a little more glue and replace the cap as before. Now you are ready to finish your stones. If you have more than one cap on a start, saw them apart. Next, take a pocket knife and scrape all the excess glue away from the cap. This will help you clearly distinguish the edge of the cap. Dop the stone on the cap. If you are using dop wax, make sure the edge of the cap is visible all me way around the stone. Some people dop their stones with epoxy, also. Trim as much of the backing away from the stone as possible. Start grinding on a 600 lap at about 15 to 20 degree angle so that you under cut the cap. With a little practice you will be able to trim just under the edge of the cap without touching it. This eliminates having to polish the cap. The backing should also be trimmed down to about one-sixteenth of an inch thick. If you are not using the pre-cut caps, glue the slab of quartz on the start, mark out the size of the stone you wish to make and cab just as you would a piece of quartz. Claudia Haight, Spencer Idaho, Idaho Opal Mines. Tips on triplets Many people ask us which is better to use-a high or low dome cap. We use which ever type does the most justice to the stone. A simple rule to follow is this: Try placing both kinds of caps on the start while you still have the fracture sealer on it. This will give you an idea of what the finished stone will look like. Hold the start at eye level and look through the side of the caps. If all you see on the high dome is clear quartz then it is probably best to use a low dome. A high dome should pull the color into the top of the cap so the color is visible from all angles to be effective. The backing material doesn't have to be black. A red material such as jasper is in, effective with some types of fire. Also plain white opal can be used to give the triplet a "natural opal" look, but also the protection of a triplet. Quartz on both sides is very desirable for pendant mountings that may turn over when worn. Always remember that one of the biggest enemies of triplet is oil. Be sure to thoroughly clean each piece that may have come in contact with any. Don't forget that there is oil in your skin, too. Any piece you touch should be cleaned, also via Thunder Bay Gems. An Opal Mosaic Triplicate Gather your small opal chips that you have no other use for and make yourself an Opal mosaic triplicate. Prepare a backing of obsidian or some other suitable dark material; about 1/16 inch thick and just a little larger than the shape of the cabochon you unit to make. Sand the surface flat, but do not polish. Do the same with a clear piece of quartz, about 3/32 or 1/8 inch thick. On the sticky side of a piece of masking tape, mark the size and the pattern you want to make. Then place the opal chips on the tape in a mosaic fashion. Fit each piece close together. Try to use nice pieces of fire and nearly all the same thickness which can be 1/32 or 1/16 of an inch thick. Let the edges overlap the design where necessary, as those will be shaped off in the cabbing. Next use black epoxy cement or mix clear epoxy cement with a little lamp black and rub it on the opal and in between the spaces. Use a toothpick. Rub additional epoxy mixture on the backing piece and press onto the opal chips. Let stand until cured, usually 12 to 24 hours. Shape form the cabochon so that the bezel of the mounting will cover the edges of the opal. You may have to thin the backing a little. Put a nice polish on the quartz face and the result should give you a colourful cabochon ready for mounting. via Laphound News Fire obsidian Did you know that a chunk of black obsidian you have just might have gold sheen, fire, or moon glow in it if you orient it correctly? Take it out into the sunshine and try to locate a spot that shows something more than just black. If yours has a rind or film on it, take a small chip off here and there. Then wet the piece and turn it slowly in all directions so the sun will reflect any unusual coloring. If you are fortunate enough to find color, orient it by using the Sinkankas method of a single light bulb over your head so the light just grazes your forehead. Mark your piece and saw it. Check before sawing each time to make sure that you are keeping the color on top. Fire obsidian can be so colorful that you will think you are looking a at black opal. via Laphound News How to get an eye in tigereye Tigerye is a hard siliceous or quartz family gemstone, with hardness of 7 on Moh's scale. In cutting parallel to fibres, a difference of 2 or 3 degrees will noticeably reward you. An improper cut is soon recognised. Now look across the slab at a 60 degree angle, a light or dark area should appear, with the dark on the farther side. China pencil mark a dividing line, each side should be a different color. 1.Hold the slice in the same plane, turn end for end, the light area should prevail nearest you, and the dark farthest away or on the opposite side as before. Again mark a dividing line, it is at the same division area. 2. Turn the slab over, top for bottom, and the reverse lighting is apparent. The dark is on the side closest to you, even if the slab is turned the dark should still be closest. As in (2) the dark area observed at 60 degrees is the top of the stone you wish to finish. As in 1) template marking will be where light half and bottom of cab. A floating eye of light will result. Al Bodman Victoria Stone -This beautiful, newly constructed stone is mineralogically similar to nephrite jade. It is substantially quite compact and tough, despite its remarkable crystalline nature. It is laboratory produced from natural minerals such as quartz, calcite, fluorspan, magnesite, feldspar, etc. These minerals are fused together in a sufficiently high temperature to a molten magma, and again mineralised under the effect of special crystalisers and crystal habit regulators to a new mineral of fine fibrous aggregate structure, mineralogically belonging to the amphibole group. This is not a synthetic or imitation, but is a reconstructed natural stone. While it is mineralogically similar to nephrite jade, the arrangement of the actinolite crystals is not the same. Instead of crystals interlocking and tying together as they do in jade, they have crystallised in fan shapes thereby providing the characteristic brilliant chatoyancy of the stone. The stone has a hardness of six on the Mohs scale and a specific gravity of 3.02, with a refractive Index of 1.62. Tips on sanding and polishing After shaping, sand and polish by hand . . . as a matter of fact, in your cupped hand, very carefully. Polish on the wrong side of the leather, using cider vinegar, Linde A, and tin oxide. via Chips and Tips ***New as of Dec 30. 1998 TAGUA NUTS VEGETABLE IVORY A true ivory, known to have been used for over 125 years. It is the exceedingly hard kernel of a nut produced by a palm. It grows in northern South America, botanical name: Phytelephas macrocarpa. Found in dense thickets near or along rivers, the tree may reach heights of 20 to 30 feet. From eight to thirty nuts are massed in large thorny heads, resembling enlarged chestnuts, and may be found growing at ground level, or a few feet above the ground, or in the top of the tree, depending on the subspecies. About 1859, ships returning to Germany from South America carried tons of Tagua nuts in their holds as ballast. Some of these found their way into the hands of skilled Austrian carvers, who made beautiful hand-carved buttons from them. By 1860, ivory buttons were in demand, and Schnollen, Germany, became the centre of ivory buttons were made in many forms dyed and natural, shiny and dull finish, metal rimmed, carved and stamped. Probably your grandmother, or great-grandmother, used ivory buttons made from the Tagua. In the early 1900's, experimentation with plastics developed, and within a few years, cheaper plastic buttons foretold the end of the ivory button industry. The use of Tagua nuts for carvings and figurines continued in the Orient. Today, many would like to work with ivory- to slab, carve, cab, or scrimshaw, but scarcity, high cost and endangered species has turned us back to the Tagua nut. WORKING WITH TAGUA It handles, cuts, ages and works just like animal ivory. TO CUT: Use any small saw- hacksaw or similar. Cut dry. Do not use your diamond saw --it is a waste of time and the nut may absorb oil. TO GRIND: A worn 80 or 100 belt will remove saw marks. T0 POLISH: A worn 400 or 600 belt, used dry, will polish, or you can use any white polish and your favourite buff. Use a little moisture here. CAUTION: Treat Tagua nut ivory very gently - do not overheat in working. Suitable for slabbing, cabbing, carving, scrimshaw - just use your imagination. Your Tagua nuts are thoroughly dried and cured ready to use. Western Gem and Mineral Supplies, 1. Abalone shell layers can be removed by using nitric acid to expose the colors, and then neutralising it with ammonia. Avoid inhaling the dust when grinding and polish, finally, with cerium oxide. via Slabs & Cabs,Gem Drops & Stonebruisers 2. Have you eyer wished to dye your abalone chips or howlite? Tidibowl or saniflush will do the job. It takes about three hours. Liquify cake in jar of water - put in abalone or howlite. Al Bodman 3. Plume agate undercuts readily since the 'plume' is softer than the agate. This problem can often be remedied by reducing the speed of your sanding and polishing operations. If you can reduce the speed to about one half normal, this problem should be eliminated. Also, it is suggested that you use cerium oxide on leather for the final polish. Avoid excessive heat. via Snoopy Gems 4. This works and is successful, the proportions of the stones and ratio of plastic pellets used, is the secret. Example: A 3 lb barrel and success of polish if adhered to as follows: 1 lb of apache tears (no pellets) 1 1/2 tablespoons 80 grit, water to cover and tumble for four days or long enough to remove matrix. Wash thoroughly (use sieve or colander to separate stones from grit) return to tumbler-- add 11/2 tablespoons 400 grit, 1/2 lb plastic pellets (bulk ratio of one of stone to one of pellets) water to cover and tumble for 7 days. Same procedure in washing and separation. Now add 1 1/2 tablespoons 600 grit, use same pellets and stones. Tumble for 7 days continuously. Same procedure in washing and separation. Now add 1 1/2 tablespoons of tin oxide to same pellets and stones,-- tumble 7 days. Thoroughly wash stones, add 1 1/2 tablespoons granulated detergent, plus pellets and stones. Tumble for 24 hours. The Results should bring shiny and glossy apache tears. The purpose of the plastic pellets is to act as a buffer in rotation. Should failure result, return to 600 grit arid proceed. Stick close to the cycles and quantities of grit, pellets and polish for best results. Al Bodman 5. Experiments have shown that it is possible to polish almost any material with a high polish in a tumbler - even stubborn apache tears -by using 1 pound of cerium oxide with dry cornmeal for final polish, to a 12 pound tumbler. USE DRY. Tumble 3 days. via The Geode 6. If you have some chrysocolla and would like to bring out the green and blue, also any copper, put it in liquid bleach, full strength for as long as it takes. This really works and you will get some good colors. Rock Chip Reporter via Petrified Log 1. Most of the brown debris on crystals can be removed by soaking them in a solution of oxalic acid (poisonous). However, if the acid is not available, use TSP (trisodium phosphate). This is used to clean grease from driveways, so can easily be found in almost any auto supply or hardware store. Three tablespoons in a quart of warm (not hot) water works best. (Please be sure to check safety precautions when using TSP, and if your specimen can tolerate it.) Al Bodman 2. One way to clean quartz and amethyst crystals is to cover them with fresh vinegar to remove carbonates such as calcite, barite and lime; allow to stand overnight. Repeat if necessary; wash well then place crystals in washing type ammonia for 8-12 hours; remove, rinse well, wipe and air dry. from many bulletins via The Geode 3. Jim Sanchez of San Juan Gems is able to produce an alligator skin finish on dinosaur bone. The bone is handled much like agate, sanded to 600 grit on silicon carbide, polished on felt with tin oxide. The stone is then finished with black rouge on a muslin buff. The muslin buff can clean out the tin oxide that remains between the bone cells, and the black rouge applies a stain to the tin oxide that remains. (Try red rouge) via Slabs & Cabs, Gem Drops & Stonebruisers 4. Ever thought of using round tooth picks (wooden) for holding that extra small cab, in the grinding, sanding, polishing process. Al Bodman 7. If you have an item that has been epoxied incorrectly, it can be taken apart by soaking it in household vinegar. It works and is inexpensive. Calgary Lapidary Journal 8. Powdered lampblack can be mixed with epoxy to color it for making doublets or other stones where a black background is desired. via Hy-Grader and The Geode 9. Don't try to clean fluorite by washing in hot or very warm water. Luster will vanish and be gone forever. It can be put in muriatic acid to remove calcite, then wash in cool water. via The Puget Sounder 1. Oil of cinnamon or oil of cassia sold by the ounce in drug store, has a refraction index near to that of most stone. When you submerge a stone in the oil, the surface irregularities vanish and you see the flaws and inclusions. via The Puget Sounder 2. The secret or the art of healing fractures in a cab with epoxy is to shape your stone and semi-polish it. To get rid of that nasty crack, heat the stone to 200 degrees in the oven. Mix the epoxy and apply it to one edge of the crack. Gradually apply the epoxy, working from one end of the crack to tine other. This is very important. You will notice that the epoxy becomes very liquid when it touches the hot stone and it flows right into the crack. By applying the epoxy at one end and working toward the outside edge of the cab the air is driven out. Put the stone back in the oven for 20 minutes. The epoxy will harden. Scrape off the surplus and finish polish. If done right the fracture will be difficult to detect. via Puget Sounder, Rock Rollers, Contact Zone 3. Some soft stones such as malachite and azurite can be patched to fill in small pits and cracks by taking a scrap of the material to be patched, crushing it and mixing it with epoxy. Clean the stone thoroughly with alcohol, coat the pits or cracks with epoxy, than fill with mixture of epoxy and powdered stone, working it well into the crack with a toothpick or pin, leaving a little above the surface of the stone. Let dry completely, sand wet and polish, using care not to get the stone hot in sanding or polishing. via The Geode 4. Working with dark colored moss agate, like the black Montana variety, small pits may sometimes appear on the finished, polished surface. The light colored polishing powders, such as tin oxide or cerium oxide, often pack into these small pits, asking removal difficult, arid white spots surely distract from the stones appearance. Try rubbing a small bit of black india ink into the spotted area, and then try to rub off the ink. The white spots will disappear: via Chips & Tips 5. If you would like to try your luck at stabilising a porous stone such as turquoise so it can be cut and polished, the Silvery Colorado River Rock Club offers these instructions: Take a jar with a lid; add one pint of acetone. To this, add the complete contents of both the resin and the hardening tubes of epoxy glue, mixing well. Add well dried stones, cover the jar, and leave for at least four days. Remove stones and allow a week to dry. They should now be stabilised and ready to work. The British Columbia Newsletter Suggested diamond saw speeds by blade.
via TSI inc.
1. When cleaning fern fossils do not use wax, shellac, varnish, lacquer, or spray plastic on fern fossils. These items cannot readily be removed, destroy forever the fine surface detail. Museums use yellow dextrin, it can be used on everything to bring out contrast and to help preserve the specimen. Just mix a tiny bit of the dextrin with water to the color of tea, and paint it on the fern itself, not on the matrix and it will stand out and also be preserved. The dextrin washes right off, if you wish, with no harm to the fossil. Be sure to get yellow dextrin, not white. It is available in chunks from drug stores. via The Geode 2. To clean fossils, put them in an old bucket out in the backyard and cover them with water. Then add a little Sani-Flush. After it quits fizzing, pour off the water. Repeat as required, rinse well, and dry. (Be careful where you dispose of the water.) via The Geode 3. First tumble garnets, second put one drop of "refracto" on garnet. Use a penlight and see the star. Try different faces. There is a "silk" on face, but you can not see the star without "refracto". Tourmaline and garnet both chip. Grind carefully on well-dressed smooth wheels. Both stones are fairly heat sensitive--sand wet, Linde A on leather is a good polishing combination for those gems. via The Geode 4. To find the star in your garnet, cut both ends from a # 3 coffee can. Put a 300 watt light bulb inside tin can. Make a cover with a 1 inch hole in it and put over the can with the light inside. Make a bar with holes ranging from ¼ to ½ inch. Place the garnet in the appropriate size hole. Rotate the garnet over the light coming through the 1 inch hole until the dark spot in the garnet shows up in the middle of the garnet. Mark this spot with fingernail polish. Dop onto the spot marked and shape and polish garnet. The star should be directly opposite the spot you marked. You can also dop exactly opposite the spot marked and work the stone accordingly. Either side should produce a star. via The Geode 5. Have you ever wanted to polish gem. tree base of wood? Spray with gold colored paint and while wet sprinkle with baby powder. When dry rub it well to polish. via Laphound News When iron pyrite is scraped across a piece of ceramic tile, it produces a black streak, while gold leaves a band of yellow. Bill Rogers, via Puget Sounder 7. The monument maker uses a weak solution of oxalic acid to acquire the glassy shine on granite. Dissolve a little oxalic acid in water and add to your polishing past. Try it on agate. via Strata Gems The polishing of ivory As done with white tripoli. Ivory should be worked dry, as water can be absorbed and is inclined to crack and tends also to chip. Hydrogen peroxide cleans ivory of that "yellowing" color. via Laphound News 1. When working with moonstone, use high-intensity light. Grind on side where you see The light flash. That will usually give top or bottom. Cut moonstone against the cleavage plane. Be sure to grind it on a smooth wheel. It polishes nicely on felt with cerium oxide. from many bulletins via The Geode 2. Mother of pearl for inlay work can be softened by soaking in white vinegar. It then can be cut easily, saving much time. via The Geode 3. When grinding stones which chip easily such as obsidian, etc. cover base with sticky-tape before dopping. Then work top of stone, the tape will strengthen edges and save stone and tempers. via The Australian Lapidary Magazine 4. When grinding obsidian, and sanding it, always grind from the center out; otherwise, the wheel and sanding belts pick up minute chips of glass that will scratch your stone. via Chip & Tips 5. When working with rainbow or fire obsidian, cut your slab thicker than usual, ¼ inch thick. Clean the slabs, coat with a light machine oil and hold under a strong light, to reveal the fire or rainbow. When making your cabochon, the flatter you make them, the better the fire or rainbow, shows through. (Fire shows with less orienting under the light.) Cut a 5 degree angle, to the line of flow, The color is on the black line. If you have a rock with lines running straight then runs into swirls; Cut it where the swirl starts. Cut the straight piece with the lines as much as possible. For the swirl, turn it with the lines when possible. You will get a perfect finish by dry sanding, get all the scratches out and finish with 220 grit. Then polish with cerium oxide. Hells Canyon Club 6. Instead of washing the slabs in detergent and water after sawing try using M 0 P, an oil and grease absorbent marketed by Castrol. It is a fine material, not unlike crushed rock. Bury the slab in the dry material. It will absorb any oil or grease, leaving the slab dry and ready for use, with no mess. It will last indefinitely. Any oil spilt on the floor can be "mopped" with M 0 P. via The Australian Lapidary Magazine 7. Our records show that prior to using T S P each 10" diamond saw lasted about one week during which we did about 20 hours trimming work, and over a period of five weeks our tests show that we used five saws which trimmed 1733 stones.We then continued a series of tests using T S P oil treatment on the basis of adding 71/2 ozs. to each 1/2 gallon of coolant which comprised 1 part oil to 3 parts kerosene. With the resultant coolant we were able to achieve 10 weeks life of 20 hours trimming per week with five saws, and in this period trimmed 4434 stones. North Queensland Rock Shop D; W. Simpson, Manager via The Australian Lapidary Magazine (EDITOR’S NOTE – think they mean a common oil additive with the T and the S transposed) 1. To filter your used oil, take a five gallon pail and insert an old sauce pan; Minus the handle, upside down inside the pail. The sauce pan should be about 2/3 The diameter of the pail. (EDITOR’S NOTE – check with your significant other first before removing the pan from the kitchen – without a handle it will be much harder for the doctor to remove if you didn’t ask!) place three large shopping bags, one inside the other, make three thicknesses of paper. Now place the bags inside the pail on top or the sauce pan. After draining the slump from your diamond saw, pour it into the triple bags. Place the lid on the pail and leave for as many days as required to let the oil filter through the bags. Remove the bags which now contain all the grit from sawing. The bags can either be burnt in the incinerator or disposed in the garbage can. The oil that filtered through the bags is now in the bottom of the pail. It can be poured into a plastic container for future use in your diamond saw. via Laphound News 2. If you ever need to use a pattern for a multiple use project and have to use the same shape many times, try using a soft drink can of aluminium. They are easy to cut, maintain their shape relatively consistently, and don't require a lot of work. via Chip & Tips 4. Use plastic, pump type, spray bottle for efficient and economical way to apply cerium oxide to surface of your polishing disc. Make light mixture of cerium oxide and water for use in sprayer. Leave mixture in the spray container, shake vigorously before each application. Water will not evaporate and solution can be used for a long time. via The Geode 5. Stones sometimes develop threadlike scratches while being; polished. These fine scratches may be due to some small particles of grit on the polishing cloth. To remove unwanted grit take a piece of plywood or balsa wood and hold it against the polish cloth while the wheel is in motion. Grit will penetrate the wood leaving the polish cloth clean. via The Geode 7. Many clear or transparent cabochons are not polished on the back side. Try polishing the back and observe what happens. If the cab has any inclusions the polishing makes these stand out much better. via Chips & Tips
1. After lapping flat stones, such as thunder eggs, with 600 grit, wash them and leave them under a heat lamp or 100 watt bulb for about 5 minutes. When the stones are warm, polish them on a flat wheel with tin oxide. By preheating, the polishing is almost instant. Other wise, a felt wheel has to heat the stone before the polishing action begins. via Chips &Tips 2. Silicone treatment tissues for cleaning eyeglasses do a great job for removing fingerprints from polished stones or cabs. via Chips & Tips 3. When polishing soft material and it sticks to the buff, try using vinegar instead or water. It seems to cut the surface tension which is holding the material. via Chips & Tips 4. Wood limbs and petrified wood can be polished to a glass-like finish by using tripoli on a cotton buff instead of the more expensive tin oxide. via Chips &Tips 5. Take a second look at that broken plate or piece of pottery - you right be able to make a piece of jewellery from it. Chart shows speeds obtainable from an 1725 Electric Motor
8. Rhodochrosite is soft and must be worked carefully. It is sensitive to heat and care should be used dopping it. Grinding should be done on a fine grinding wheel that is true and free from lumps. Use plenty of water to keep work cool; not much pressure is needed. Wash stone and hands before sanding. Sanding should be done wet on a fairly new 400 grit cloth to help avoid undercutting. Polishing is done on a hard leather buff with pure tin oxide and little Linde A. via The Geode 1. When you want to solder one part of a piece without having the solder into an unwanted area, try painting the area not to be soldered with a thin paste made with jewellers rouge and water. To remove scrub with a stiff brush. via The Geode 2. To get rid of excess solder, take a narrow strip of silver about 1/3 inch wide and 3/4 inch long, cut a small slit in on end. Heat the piece with the excess solder on it, and touch the slit piece of sliver to the excess solder. The excess solder will flow up the piece of silver. via The Geode 3. The best material for wind chimes is solid brazilian agate, India blackskin agate, or India red/green moss agate. Picture jasper is also verv good. Slice the material 1/8 inch thick. via The British Columbia Newsletter 4. Recommended speed for sawing, 3,000 surface feet per minute. In various literature, varying speeds, ranging from 2,000-8,000 S.F.P.M are quoted. The slower speeds are for hard stones, the higher speeds for soft stones. One diamond blade manufacturer recommends 3,000 for agate, and 5,000 for opal. 3,000 appears the most useful for the average lapidary. via The Australian Lapidary Magazine 5. Recommended speed for grinding is 3,500-4500 surface feet per minute. In one Australian abrasives pamphlet, the above speeds are recommended. Some USA literature goes as high at 6,000 S.F.P.M. .This high speed would require very good bearings, and a continually "trued" wheel. Any bumps in the wheel would create excessive vibration, and would rapidly wear any moving parts - to say nothing of potential danger from a wheel disintegrating. via The Australian Lapidary Magazine 6. Recommended speed for sanding is 2,500 to 3000 surface feet per minute. This is probably higher than a lot would recommend, and I am not intending to be provocative in quoting these speeds. Australian Abrasives, Norton, 3M Co. - they all recommend speeds in this area, and as manufacturers, they should be given heed. These speeds do work, and as long as common sense is exercised, they are not likely to cause cracks in the stone through heat build-up. (Remember, I am generalising - no account is being taken of "special treatment" which may be necessary for the occasional sensitive stone). via The Australian Lapidary Magazine 7. Recommended speed for polishing is 800 surface feet per minute. Some units on the market today may not have a large enough pulley to permit this low speed. Published speeds in books range from 500-2000 S.F.P.M. for various types of buffs. However, there seems to be a fair weight of opinion that slower speeds are more satisfactory as a general rule. via The Australian Lapidary Magazine |
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