Size of thumb stones: approx. 46 x 31 mm (approx. 8 mm thick) Handmade thumb stones in many different types of gemstones. Delivered with a description card per gemstone (German texts!) If you buy at least 72 pieces, you will receive a high-quality presentation plate at no additional cost. The stones come from all parts of the world and are cut and polished in gemstone mills around Hong Kong. The best gemstone cutters are traditionally located there.