Mass. Gen. Laws ch. 266 § 142A
Whoever is in the business of purchasing gold, silver or platinum shall enter in a book kept for that purpose a description of the item, quantity purchased, the purchase price and the name and address of the seller; provided that the purchase price of such item is at least fifty dollars. Any person who sells gold, silver or platinum shall be required to show to the buyer prior to said sale identification which includes a photograph of said seller. Said book shall at all times be open to the inspection of the chief of police of a city or town or of any other officer having similar duties or any officer authorized by either of them, or a state police officer. Whoever violates any provision of this section shall be punished by a fine of not more than one thousand dollars or imprisonment of not more than one year, or both such fine and imprisonment.
Mass. Gen. Laws ch. 266, § 142A