Thai baht of weight for precious metals and gemstones. One baht = 15.244 grams. Since the standard purity of Thai gold is 96.5 percent, the actual gold content of one baht by weight is 15.244 × 0.965 = 14.71046 grams; equivalent to about 0.473 troy ounces. 15.244 grams is used for bullion; in the case of jewellery, one baht should be more than 15.16 grams. The Bank of Thailand adopted a series of exchange controls on 19 December 2006, which resulted in a significant divergence between offshore and onshore exchange rates, with spreads of up to 10 percent between the two markets.
Precious coral Precious coral Precious coral, or red coral, is the common name given to a genus of marine corals, Corallium. The distinguishing characteristic of precious corals is their durable and intensely colored red or pink-orange skeleton, which is used for making jewelery. Red corals grow on rocky seabottom with low sedimentation, typically in dark environments—either in the depths or in dark caverns or crevices. The original species, "C. rubrum" (formerly "Gorgonia nobilis"), is found mainly in the Mediterranean Sea. It grows at depths from 10 to 300 meters below sea level, although the shallower of these habitats have been largely depleted