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Widdershins Studiotm

Widdershins Studiotm is a private lapidary workshop located near Eastover SC, about 20 miles east of the Columbia, South Carolina’s capital city. I am the lapidarist, aided by my wife Christine and -- much less often -- by our Belgian Shepherd and dozen or so tabby cats. The workshop shares space in our residence on 12 acres of secluded, wooded land replete with a pond, geese, ducks, raccoons, opossums and deer.

I've been doing lapidary work intensively for several years, as a prime avocation and a mode of relaxation. My main interest is in shaping and polishing cabochons – domed pendants worn on a necklace or as a brooch, whose perimeters are normally oval or circular -- but may also take on "free-form" shapes and contours. My cabochons are made from a wide variety of natural minerals, including obsidian, agate, jasper, jade, quartz and many other interesting material types.

I buy my raw materials in the form of pre-sliced slabs from dealers and rockhounds, usually from the Western states of Utah, Idaho, and Oregon – domestic hotbeds of great lapidary rocks and stones. However, many dealers also buy and sell much-sought-after lapidary rough from all over the globe – Brazil, Mexico, Europe, India, and even Tibet.

I've been truly amazed to find out how many hundreds of varieties there are of agate, jasper and other beautiful lapidary materials. Some distinctive varieties are often found in only one location on the entire Earth.

Rough-cut slabs may be anywhere from 0.2 to 0.3" in thickness, and range from small pieces only a few inches on a side, to larger slabs up to a foot or more across. Cutting larger rough rocks into slabs requires large, specialized (read expensive) slabbing saws. Because it's a particularly messy, time-consuming operation, I prefer (at this time) to buy most of my slabs pre-cut.

The number of cabochons that a slab can yield varies greatly, since not every square inch of the slab is necessarily usable or suitable for a beautiful final piece. Nature is far from perfect, and one must avoid soft inclusions, non-sealed fractures, bad voids, vugs, large pits and other problem areas on the slab. Plus – more importantly – unique local areas of pleasing patterns and colors fairly cry out to be selectively chosen for a uniquely stunning final cab. This means that the surface will never be "divvied up" in the most efficient way.

I lay out and mark the cabochon perimeters with a fine-tipped permanent marking pen or aluminum scratch pen, using a steel template. These marking templates contain calibrated (standard) ovals, circles and other shapes. For example, some standard oval cabochon sizes are 40 X 30 mm (my favorite), 30 X 22 mm, 18 X 13 mm, and so on. For very dark materials, I may use a fine white waterproof paint pen to do the marking.

I next trim out each marked figure, allowing some margin outside its perimeter, using a 6" circular trim saw. This is like a cute little table saw for a midget, but uses a thin, diamond-edged saw blade. (Normal ceramic saw blades like the kind that you see in Home Depot do not work. In fact, all the necessary equipment, tools and consumable materials are very specialized and must be ordered from lapidary supply houses.)

The bad part of this trimming operation is that the sawblade requires constant flooding with a special oil-based coolant – very foul-smelling stuff. As the saw blade rotates under the worktable of the trim saw, it plunges through a reservoir bath filled with oil and pulls some of it around with it over the top again, onto the workpiece – while also slinging it all over the human operator as well, since the splash guards are not very effective. There is also a small feed vice and guide rail that can be used with this type of saw, to allow it to do slabbing on very small pieces of rough. I've used this feature from time to time, but it's limited to rough rocks and stones no more than about 2-1/2" in diameter.

After washing the cut-out "preforms" with soap and water – and remarking the cab outlines if necessary – it is time to begin the cab shaping operation. I use a 6" horizontal polishing machine that uses a constant water drip-flow as coolant. It is variable-speed drive, up to about 3,000 RPM. I do the basic shaping of the cab perimeter and curved surface contours using a solid steel, diamond-impregnated, 180 grit wheel. I do this by hand, and do not use a dop (extension) stick – I've learned how to keep my pinkies always just clear of the rapidly spinning wheel surface – at least, almost always. I obtain the curved surfaces using movement techniques that I can't easily explain or describe. Suffice it to say that the touch and feel for this took a good long time to acquire and develop fully. The technique used must also be adjusted according to the hardness of the material, and whether it includes both hard and softer minerals in the same cab.

With the basic shape of the cab established, I replace the unit’s hard shaping wheel with new wheels, upon which are attached 325, 600 and 1200 mesh grit diamond-impregnated sanding disks. These are adhesive-backed disks so they can be replaced when spent. For final success, all grinding marks from the previous shaping or sanding wheel must be fully removed before sequentially moving on to the next finer disk. This takes time and lots of patience.

The final polish is normally done using a wheel with a dense, hard cotton fiber pad attached. The polishing is also performed wet, using either cerium oxide powder (if a hard stone) or chromium oxide (if a softer material). To get the best luster I can on softer materials, I sometimes use a rough leather disk on the wheel, rather than the flat cotton pad.

If the final stone is a calibrated size, I may mount it in a commercially purchased plated gold or silver hoop or clasp. If the cab is a non-calibrated or a "free-form" shape, I'll drill a small hole (using – you guessed it – a special diamond-impregnated drill point) and attach a simple wire-wrapped loop and jump-ring to use with a necklace chain.

The entire process may take anywhere from 2 to 3 hours per cab. Considering the cost of consumable items – for example, those 180 grit hard shaping wheels run $80 a pop – and thinking about the man-hours involved -- it is certainly not a way to get rich.

But when I view the natural beauty of the finished cabochon – I know it's definitely a way to get happy…


 Click Here to See Some Cabochons...

 Image at top of page is a closeup of a section of a Crazy Lace agate slab.


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