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Designer Malachite Cabochon

Designer Malachite Cabochon
Denise Harrison

Collector designer cabochons are large cabs that are created to maximize the potential that any material has to offer. These cabs are a nice addition to any collection. Due to their size, they display well in any collector’s cabinet or shelves.

Inspiration comes from the most unusual places. The sharp points and curves on this cabochon is inspired by my cat, who likes to rub his fang on my cheek.

I prefer to use a thicker slab of material so I can create a higher dome, resulting in a shinier surface. Low-domed cabochons do not attract as much light. I sketch my pattern onto the back
of my slab using an ultrafine permanent marker. I use my Genie diamond hard wheels to shape my cabochon. The shape will be the foundation of my work and the lower bevel line.

The curve in the cabochon is created by holding the slab’s edge against the diamond hard wheel, either 80 or 100 grit. I use gentle pressure to allow the diamonds to do their work. I grind until I have achieved the desired curve for my design. Then, I proceed to the outside curve, paying special attention to the area where the inside curve meets the outside curve. I want a well-defined point at the end of my cabochon.

After the lower bevel has been established, I draw a line one third of the distance from the bottom of the material. This line is where the top of the bevel ends and the dome begins. Now I grind my way around the top edge of the cabochon, creating my dome on the upper two thirds of the stone.

I visually inspect my work by rotating my cab so that my dome is in the center and my angle is the same all the way around the cabochon. I remove all the trim saw scratches, fractures,
pits, and unattractive imperfections.

When my dome is complete, I move to the 280, 600, 1200, 3000 and 8000 soft diamond wheels of my Genie to remove scratches from the previous wheel. I use a magnifier to inspect
the cabochon before moving to the next wheel. This important step will ensure that my end result will be flawless and I will achieve the maximum polish the material has to offer.

I like to finish the back of my cabochon by removing the sharp edge and any nicks by holding the back of the cabochon at a sharp angle on the 600 diamond grit wheel, using gentle
pressure. I remove the permanent marker line, as well, by holding the back of the cabochon flat against the 600 diamond grit wheel.

Malachite is a soft material (Mohs 3.5-4), so I used 8000 grit diamond wheels for my final polish. My cabochon measures 26 mm by 59 mm by 8 mm.