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.
Money and at one point there was bronze as well. Now we have copper coins and other non-precious metals as coins. Metals were mined, weighed, and stamped into coins. This was to assure the individual taking the coin that he was getting a certain known weight of precious metal. Coins could be counterfeited, but they also created a new unit of account, which helped lead to banking. Archimedes' principle provided the next link: coins could now be easily tested for their fine weight of metal, and thus the value of a coin could be determined, even if it had been shaved,