Step-by-Step Instructions
1. Safety first: wear safety goggles, a dust mask, and rubber gloves to protect from dust and debris.
2. Outline your desired cabochon shape on the stone with a marker pen.
3. Using the Dremel with a coarse diamond grinding bit at low to medium speed, carefully rough shape the stone, following your outline. Keep the stone wet by spraying water frequently to avoid overheating and cracking.
4. Switch to a medium grit diamond bit to refine the shape and start forming the dome. Continue to keep the stone wet.
5. Progress to a fine grit diamond bit to smooth the surface further, maintaining a gentle touch and water lubrication.
6. Use silicon carbide sanding bands starting with 400 grit, then 600 grit, and finally 1200 grit to sand the surface evenly, smoothing out scratches and achieving a near-polished finish. Keep the stone wet throughout.
7. Attach a felt or ceramic polishing wheel to the Dremel. Apply a small amount of cerium oxide or jeweler's rouge polishing powder to the wheel.
8. Polish the stone at a low speed, gently moving the stone against the wheel. Keep it wet if possible and polish until the surface is glossy and smooth.
9. Wipe the cabochon clean with a soft cloth.
10. Inspect for any imperfections and repeat sanding or polishing if needed.
11. Allow the stone to dry completely before setting into your chosen jewelry setting.