This Guide is a basic guide on the most common precious metal purity hallmarks. All precious metal items should still be professionally tested to ensure purity no matter what they are marked, as hallmarks can and are faked. Platinum Hallmarks: Common Platinum Hallmarks: Platinum, Plat, Platine, PT, 750, 850, 900, 950, 999 When dealing with the number hallmarks you must test to ensure you are actually dealing with platinum rather than silver. Often a platinum hallmark will be followed by its "base metal", for example a item may be marked 900 PLAT 10% Iridium; Indicating it is 90% Platinum with 10% Iridium as a Base. Gold Hallmarks: Solid Gold: 8 Karat Solid Gold ~ 333 ~ 8kt ~ 8ct = Indicates the item is 33.3% Pure Gold 9 Karat Solid Gold ~ 417 ~ 9kt ~ 9ct = Indicates the item is 41.7% Pure Gold 10 Karat Solid Gold ~ 417 ~ 10KT ~ 10K ~ 10CT = Indicates the item is 41.7% Pure Gold 14 Karat Solid Gold ~ 585 ~ 14KT ~ 14K ~ 14CT = Indicates the item is 58.5% Pure Gold 18 Karat Solid Gold ~ 750 ~ 18KT ~ 18K ~ 18CT = Indicates the item is 75% Pure Gold 21 Karat Solid Gold ~ 875 ~ 21KT ~ 21K ~ 21CT = Indicates the item is 87.5% Pure Gold 22 Karat Solid Gold ~ 917 ~ 22KT ~ 22K ~ 22CT = Indicates the item is 91.7% Pure Gold 23 Karat Solid Gold ~ 958 ~ 23KT ~ 23K ~ 23CT = Indicates the item is 95.8% Pure Gold 24 Karat Solid Gold ~ 999 ~ 999.9 ~ 24kt ~ 24K ~ 24CT = Indicates the item is 99.9% Pure Gold Also, in less common items you may find pieces stamped 500 for 12 Karat Solid Gold, 583 for 14 Karat Solid Gold, 625 for 15 Karat Solid Gold, 916 for 22 Karat Solid Gold, or 1000 for 24 Karat Solid Gold Silver: 800 ~ Indicates the item is 80% Pure Silver 813 ~ Indicates the item is 81.3% Pure Silver 830 ~ Indicates the item is 83% Pure Silver 900 or Coin ~ Indicates the item is 90% Pure Silver 925, .925, STER, or Sterling ~ Indicates the item is 92.5% Pure Silver 935 ~ Indicates the item is 93.5% Pure Silver 950 ~ Indicates the item is 95% Pure Silver 958 ~ Indicates the item is 95.8% Pure Silver 980 ~ Indicates the item is 98% Pure Silver 999 ~ Indicates the item is 99.9% Pure SilverTheir are also various foreign hallmarks which use images to display certain purities. A good example is the Lion Passant, a Lion with its Tail Raised, which indicates Sterling Silver. Another is the French marking system which from 1838 to 1961 used a Boar's Head for 800 Silver, a Eagles Head for 18 Karat Solid Gold, or a Dogs Head for Platinum. Their are countless more examples of such markings. If you can't locate any purity hallmark on your item, yet you do find other markings; you should contact knowledgeable sources to see if these markings have meaning. Also, do not confuse the Mexican Eagle hallmark with this French Eagle hallmark.Also, some antique items or hand-made items may not have any hallmark at all indicating purity; yet still be a precious metal item. The same can be said for items that have undergone repairs, especially rings undergoing sizing, may still be a precious metal but have lost their purity mark due to these repairs. If you think your item is possibly a precious metal, take it to a professional to be tested.Items marked Gold Filled, Filled, GF, RGP, Rolled Gold, Rolled Gold Plate, HGE, GE, GO, GEP, HGP, HGEP, Plated, Layered, and Flashed marked gold items are NOT Solid Gold. Gold Filled and Rolled Gold items have minor refinement value; plated marked items have little to no refinement value.Sterling Items Marked with Vermeil, Washed, Overlay Indicate that they are Sterling Silver that have been covered in a layer of Gold and they have NO Gold Value; only Silver Value.Items Marked Alpaca, Nickel Silver, German Silver, Argentan, new silver, nickel brass, albata, alpacca, or electrum are NOT Real Silver and have no refinement value.Items marked P4SR Contain Silver, Platinum, Palladium, and Gold; and are Mostly Silver (80-97%); with little to no gold, silver, or palladium refinement value.This guide is intended to be a helpful reference to determining the POSSIBLE purity of your item. None of this information is meant to be set in stone, and is to be used at your discretion. I am not responsible for misuse or misinterpretation of this information. I can't stress enough, if your item is marked any of the above then you should still have it tested by a professional to ensure it is the purity you believe it to be; and never just hope for the best.