Under R.I. Gen. Laws chapter 6-11.1, any business that buys gold, silver, platinum group metals, precious stones or items containing them from the public for resale, including pawnbrokers and secondhand dealers, needs a license from the attorney general. Coins bought for their collector value rather than their metal content are outside the chapter. The shop must post the per-ounce prices it is paying where you can see them and weigh your items in front of you.
You show photo ID with your date of birth and current address and sign a statement that you own the items (or are the owner's authorized agent) and how you got them. A minor must come with a parent or legal guardian. The dealer records the date and hour, your name, address, phone number and date of birth, a copy or digital image of your ID, and a description of each piece with any serial numbers or marks, sends those reports weekly to the local police chief and the attorney general, and keeps them for one year.
Everything bought is then held unaltered for 14 days from the day police or the attorney general receive the report, whichever is later, and police can extend that by 15 days if they have probable cause an item was stolen. Bullion coins, bars and medallions without serial numbers or other identifying marks are exempt from the hold. Breaking these rules is a misdemeanor, and the chapter sets no cash or check limit on how you are paid.