As a professional gold buyer and a seller, I had to know all about jewelry markings in order to buy and resell scrap gold jewelry for profit. Most folks don't know what these mysterious combinations of numbers mean. It can be even more confusing if there are letters involved as well. Caratage and Fineness: Understanding Gold Purity
Since pure gold is too soft to use for jewelry making, it is comb
ined with other metals to make it stronger. Caratage and fineness both refers to the purity of gold in a gold alloy. Caratage signifies the number of karats in it, whereas fineness refers to parts per thousand of gold in an alloy. Each gold variety (from 8K to 24K) has both a caratage and a decimal fineness. Pure gold equals 24 karats, or 24k, a caratage that can also be expressed in decimal form as .999 fine. Gold can never be 100% pure since there are always some impurities in it. The finest gold ever created was .999999 fine. The decimal is found by dividing the actual caratage by 24, the most carats gold can have. For example:
14 karat gold is .583 fine because 14/24 = .583. It is 58.3% gold, and 583 parts out of 1000 are pure gold. Therefore, the gold markings of 750, 585, and others refer to the purity of gold and correspond with a caratage. Gold Purity Markings: Common Stamps
Here is a list of common gold markings. Notice that the marking 585 is associated with 14K (14 karat) gold. In the example above we found that 14K gold is actually .583 fine. However, a 585 gold marking is also used to indicate 14K gold. The same applies to the marking 417, which indicates 10K gold, and 917, indicating 22K. Since gold standards vary around the globe, there are some other consistencies like this that you'll find if you continue buying and selling gold. Gold Markings and Their Significance
The Marking
What It Means
333-----------------8K Gold
375-----------------9K Gold
416 or 417------10K Gold
500----------------12K Gold
583 or 585--------14K Gold
750-----------------18K Gold
916 or 917---------22K Gold
999------------------24K Gold
