What Do The Markings Inside Jewelry Mean?
Have you seen any of these markings and wondered what they mean?
.417, .565, .585, .750, .925, 9ct, 10Kt, 14Kt, 18Kt, S/S, G.F., H.G.E.
Silver, Sterling, R.G.P., Plat, 10%Irid 90%Plat
What is karat gold?
24 karat Gold (also stated as 24K or 24Kt.) is 24 out of 24 parts gold or 100% pure gold. Another way of expressing gold content is .999 fine gold (999 out of 1000 parts gold).
18 karat or 18Kt gold is 18 out of 24 parts pure gold mixed with 6 parts of an alloy. 18kt can also be expressed as .750, and is 75% pure gold and 25% alloy.
14 karat or 14Kt gold is 14 out of 24 parts pure gold mixed with 10 parts of an alloy. 14kt can also be expressed as .585. In the past 13.5 karat was an acceptable alloy marked .565, and was sold as 14kt gold, today this is no longer used. 14kt gold must be .585 gold content and is considered to be plumb, sometimes marked as 14KP, which unfortunately confuses some consumers who mistake the P for meaning plated..
10 karat or 10Kt gold is 10 out of 24 parts pure gold mixed with 14 parts of an alloy. 10kt can also be expressed as .417.
Other karats of gold are common in different parts of the world, 9 karat (also marked 9ct) is common in England or Ireland, 22 karat is common in India and several other countries.
Changing the elements in the alloy may change the color or the hardness of the finished gold but it does not change the karat.
What is Gold Filled?
Gold filled means that an item has a layer of karat gold bonded on the outside of another metal called the base metal. The process used, and the base metal, may vary, but the gold content will be indicated by a fraction such as "1/20th 12Kt G.F." meaning 1/20th of the weight of the product is 12Kt gold. Rolled gold plate is a form of gold filled commonly used in the manufacture of older watches. The backs of watch cases were marked 10K R.G.P or 14K R.G.P. to indicate the content of the gold in the outer layer.
What does "Gold Plated" mean?
Gold plated usually means there is no actual gold content unless it is preceded by the karat, such as 18Kt gold plated or 18Kt H.G.E. (heavy gold electroplate). This process usually results in a very thin layer being applied to the base metal which is measured in thousandths of an inch.
What is Sterling Silver?
Pure Silver is .999 fine
Sterling Silver is .925 fine, or stated another way, 92.5% Silver and 7.5% alloy. The small amount of alloy added Sterling Silver makes the Silver more durable. Sterling Silver is typically marked "Sterling" or .925 and abbreviated as S/S.
Nickel Silver is a misnomer because it is silver in appearance, but it contains no Silver. Mexican Silver is typically about 90% Silver.
Vermeil is Sterling Silver with a heavy 14Kt gold plating.
What is Platinum?
Platinum is the noblest of the noble metals. Platinum is a white, hard and very dense metal. Platinum is usually alloyed with Iridium (90% Plat. and 10% Iridium) and more recently Cobalt is being used in Platinum alloys. Platinum is the namesake of the Platinum group which is a category of five noble metals including Platinum, Palladium, Iridium, Rhodium, and Ruthenium.