Gold identifying markings on vintage jewelry..... You want to buy what looks like a high quality vintage or antique gold jewelry piece, but it doesn't have a gold stamp. So you think it can't be genuine gold. What many people are not aware of is that many, many older jewelry pieces don't have a gold stamp mark. Much gold jewelry from both the 19th and 20th century are unmarked. Sometimes pieces from out of the country may not have markings. It was only a couple of decades ago that the US government set standards for new jewelry retailers to mark. It was not until October, 1981 that an FTC amendment went into effect tightening quality mark standards. Prior to that time, the industry has much looser standards. This ammendment only effected US trade. Other countries are different and there are no worldwide standards. Each country is has their own standards.
For pieces that are unmarked, gold purity can be easily tested by devices that measure electrical conduction, or chemically testing the reaction with dilute acids, which will determine Karat weight. Since many jewelry items still exist today that are unmarked, you must be careful what you buy not based on the fact the there is not a goldmarking. Unmarked jewelry can be easily affixed with 18k, 14k, or 12k gold tagging from an unscruptulous seller. Tags can be purchased and placed on anything that looks gold and most buyers assume since it is tagged, it must be real. Be careful to buy from only trusted sellers and to only use paypal when paying for fine jewelry.
Karat or Carat weight measures for gold purity or fineness:
24 karat (24K) - highest qualilty of gold, which is considered pure gold or solid gold, and must be at least . Pure gold is much softer than gold mixed with other metals and difficult to use for some jewelry pieces. Most jewelry gold is mixed with an alloy to provide strength.
18 karat (18K) - contains 18 parts gold and 6 parts other metals, which makes it 75% gold and 25% other metals*.
14 karat (14K) - contains 14 parts gold and 10 parts other metals which makes it 58.2% gold and 41.8% other metals*.
10 karat (10K) gold contains 10 parts gold and 14 parts other metals, whic makes it 41.7% gold and 58.3 other metals*.10k gold is the minimum karat weight allowed to be designated gold in the United States.
European Markings for Gold
18K gold is marked 750 to indicate 75% gold
14K gold is marked 585 for 58.5%
12K gold is marked 417 for 41.7%