Austin Moore on repolishing with a Dremel type tool

[SwordfishMining]

He uses a felt tip markers like a sharpie all the time in gem cutting. They help you to see where you have cut and not cut yet, as well as find small chips, cracks, scratches. When faceting it also help with meet points.



A hydrophane opal will absorb that Sharpie. Beware of anything except good solid no cracks, sand or pits opals. Ive used pencil on agate cabs before between stages of grinding for the same purpose.