I have explained before why I retired from making markets in gold — the IRS declared me to be a BANK! When gold was legalized in 1975 and began trading on the COMEX in New York, the New Jersey Senate asked me to write the law on gold to make sure it would not be taxable to buy and sell gold bullion. I worked with Senator Foran and developed the language that "gold was not taxable unless converted to use."
I was making the market to buy gold scrap from all the stores you see with "WE BUY GOLD" signs. They buy the jewelry and it has to be refined. To do that, you needed a minimum lot of 100 ounces, which was the contract size on COMEX. When gold was $800, that meant one 100 ounce bar was valued at $80,000. The refining period was 6 weeks. Therefore, all of these small operations could not afford the float. If they bought 100 ounces per week, then they would need $560,000 in working capital. That would not work for most of these small shops buying gold.
I made the market. The shops could ship whatever they bought that day and I would buy it at the daily price. I gathered all the gold sold by countless stores. The gold was shipped by armored cars to Englehard for refining (PhiBro or Philipps Brothers who eventually bought Saloman Brothers). I was doing tens of millions per week back then and refined a mountain of gold.