The gold market in New York and Chicago developed in the mid-1970s. The main reason is that after 1977, the dollar devalued, and the Americans (mainly corporate groups) made a rapid development of gold futures in order to hedge and increase investment value. At present, Comex and IMM are the largest gold futures trading centers in the world. The two exchanges have a great influence on the gold price in the spot market.
Take the New York Mercantile Exchange (Comex) as an example. The exchange itself does not participate in the trading of futures, but only provides a place and facilities, and makes some regulations to ensure that both parties to the transaction conduct the transaction on the premise of fairness and rationality. The Institute has a very detailed and complex description of the weight, color, shape, upper and lower limits of price fluctuation, trading date and trading time of gold for spot and futures trading.