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 metal coinage. Other precious metals include the platinum group metals: ruthenium, rhodium, palladium, osmium, iridium, and platinum, of which platinum is the most widely traded. The demand for precious metals is driven not only by their practical use but also by their role as investments and a store of value. Historically, precious metals have commanded much higher prices than common industrial metals. A metal is deemed to be "precious" if it is rare. The discovery of new sources of ore or improvements in mining or refining processes may cause the value of a precious metal to diminish. The status of a