0.6 troy ounces/19.5g. Maker: Untraced Maker's Marks. Andrew Campbell founder and owner of AC Silver has been dealing in antique diamond & gemstone jewelry and antique sterling silver since 1977. In addition to his high quality Newcastle-based shop, Andrew has developed what is now an established and internationally recognised online store.All orders placed before 2pm GMT are dispatched the same day. Company Name: AC Silver Unlimited.