ทับทิม, sapphires and emeralds are all colored high-end gems and are relatively expensive. ดังนั้น, the gemstones inlaid in jewelry are generally small, most of which do not exceed 1 กะรัต (เกี่ยวกับ 5 มม. x 7 mm in size). Such a small gemstone is no problem for making rings, but it is too small for making [...]
