Due to safety concerns, proper instruction on equipment use is mandatory for everyone who participates. Lapidary Procedures must be followed. All beginning participants must first take a one class Lapidary Certification Course (or otherwise demonstrate proficiency) and Quiz, which covers lapidary techniques and equipment safety and use.
Have Fun be Safe
Lapidary involves cutting and carving semiprecious stones and has similar risks as hard stone carving. Stones carvedinclude garnet, jasper, jade, agate, travertine, opal, turquoise and many others.
1. The dust from quartz gemstones such as agate, amethyst, onyx, and jasper is highly toxic because they are made of silica. Other gemstones such as turquoise and garnet may be contaminated with substantial amounts of free silica. Opal is made of amorphous silica, which is slightly toxic by inhalation. 2. Gem cutting machines can create very high noise levels.
1. See stone precautions above. 2. In the absence of adequate local exhaust ventilation, wear NIOSH-approved toxic dust respirator for sanding, grinding, or polishing operations that create dust. Use wet grinding processes.
Stones can be finished by grinding, sanding, and polishing, by either hand or with machines. Polishing can use a variety of materials, depending on the hardness of the stone being polished. Polishing materials include carborundum (silicon carbide), corundum (alumina), diamond dust, pumice, putty powder (tin oxide), rouge (iron oxide), tripoli (silica), and cerium oxide.
1. Grinding and sanding, especially with machines can create fine dust from the stone which is being worked. There are also inhalation hazards from grinding wheel dust (especially sandstone wheels). Some polishing materials such as tripoli are highly toxic if inhaled in powder form.
1. In the absence of adequate local exhaust ventilation, wear NIOSH-approved toxic dust respirator for sanding, grinding, or polishing operations that create dust.
NOT SIGNIFICANT OR SLIGHT HAZARDS, VERY SMALL AMOUNTS FREE SILICA
alabaster, amber, bone ash, calcite, carborundum, diamond, dolomite, gypsum, hematite, jade, marble, putty (tin), travertine, whiting, wollastonite.
MAY CONTAIN LARGE AMOUNTS FREE SILICA
clays, feldspars, garnet, granite, greenstone, quartz (agate, amethyst, chalcedony, chert, flint, lapis lazuli, lepidolite, onyx, silica flour) opal, pumice, rouge (if silica-containing, iron), sandstone, slate, silica-containing African wonderstone, talc, tripoli, turquoise.
CONTAINING OTHER MODERATE TO EXTREMELY TOXIC INGREDIENTS
asbestos, carbon black (if contaminated with polycyclic aromatic hydrocarbons), cerium oxide, cerrusite (lead), coal, corundum (aluminum oxide), cryolite, erionite (zeolite), fluorspar, lapis lazuli (ingestion may create hydrogen sulfide), litharge (lead), malachite (copper), serpentine (may contain asbestos), soapstone (talc), talc (can have asbestos-type materials), vermiculite (asbestos), witherite (barium), zirconia (allergen)Read more: http://andy321.proboards.com/thread/27324/lapidary-safety#ixzz4JcM8fji7
Apart from figurative carving, there are three broad categories of lapidary arts. These are the procedures of tumbling, cabochon cutting, and faceting.
Lapidaries use slab and trim saws. The difference is the size blade they use. Trim saws have small, thin blades that remove a minimum of material. Slab saw blades are thicker because they are designed to do heavier cutting. Trim saws use 4” to 6” blades that run between .004” and .012” thick. Slab saw blades run from 6” to 36” with thickness of .025” to .200”.
Grinding Wheels/ Hog
A grinding wheel is very powerful and if you know what you're doing and have the physical strength to press hard continuously, you can really hog off material fast on one of these heavy duty 8 inch grinders spinning a 100 grit diamond wheel.
Once you have completed the major cutting of your stone you will begin to use the Higher and finer grade wheels to remove scratches and evenutaly polish the gemstone. After the hog the next step is sanding with a 220 grit carbide belt on a water cooled sander with expandable rubber drums. The 220 grit belt is used to remove the scratches left in the surface of the cab by the 100 grit diamond wheel. You will eventually work your way up to a 3000-14K grit wheel for final polishing.
Gemstone faceting is a marvelous amalgam of engineering and art. Through a mechanical process of cutting surfaces on a piece of crystal, beautiful gems are created. To beginners,faceting may appear very complicated, but that isn’t really the case. Faceting does have complex subjects, like competition cutting and design. However, you don’t need to enter these areas. Learning the standard cuts is within the reach of almost everybody. The primary requirements are a desire to learn and the ability to follow instructions.