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Quick Reference

sterling silver: STER, STERLING, 925, 925Ster

gold:
18k 750
14k 585
10k 417

Platinum: PLAT, PT950
Platinum/Ruthenium: 90/10Pt/Ru, 900Pt, Pt900
Palladium: PD950, 950Palladium, 950Pall, 950Pd
Titanium: TI
Tungsten: Tungsten-carbide
gold filled: 1/29 12kGF
possible plating: no stamp

Sometimes we find a piece of jewelry that we really like because of its appealing design or striking gemstone, or for whatever reason. Maybe it’s a diamond pendant or dangle gold earrings or a shiny silver pin.  But we don’t always pay attention to what the piece is made of.

Manufacturers are not required by law to indicate what kind of metal their jewelry pieces are made of, but if they do, they are required to also include their manufacturer’s stamp. This is why, when you look at a piece of jewelry, you find stamps like “14k BCD” or something equally obscure- sometimes with a tiny piece of artwork instead of letters.

GOLD:
Karat is a measurement of the fineness of gold, and runs from 1 to 24, with 24karat gold being 100% pure gold. Pure gold is far too soft for most jewelry applications. So, other metals are added to pure gold to get an alloy that is durable and strong, yet still brilliant. The type of metal added determines the properties of the final alloy. For example, adding nickel or zinc gives us what we call “white gold”. Adding copper results in “rose gold” or “red gold”. Adding silver turns the gold “green”. There are other combinations, but those are the most common. Rose and green golds are almost always 10k, because the more gold you add to the mix, the less color is apparent. 18k rose gold has just a hint of rosiness, where 10k rose gold is quite red-looking.

Jewelry with less than 10k gold can not be legally sold as karat gold jewelry in the US. Gold jewelry in the US is usually made from either 10k (10/24, or 41.7% pure), 14k (14/24, or 58.5% pure), or 18k (18/24, or 75.0% pure) gold. Karat stamps are either the karatage or the purity percentage. Ten karat gold is stamped “10k” or “417″; 14k gold is stamped “14k” or “585″; and 18k gold is stamped “18k” or “750″.

SILVER:
Silver jewelry is almost always made from Sterling Silver, which is 92.5% pure silver and 7.5% other metals added for strength and durability. Sterling silver is typically stamped “925″ (which indicates 92.5% purity), but is sometimes stamped with the words “STERLING” or “STERLING SILVER” or “STER”. They all mean the same thing.

FILLED/PLATED:
It’s always important to read every bit of the stampings.
Gold Filled jewelry typically reads, “1/20 12kGF,” which means at least 1/20 of its weight is 12k gold. The other 19/20 is some other metal.
Gold Plated jewelry is made from a metal other than gold, which then has a fine layer of gold applied to its surface. Gold plated jewelry is typically not stamped.

Another common type of plated jewelry is called “vermeil”, which is Sterling Silver plated with gold. It will look like gold, but will be stamped “925″ or “STER”.

PLATINUM:
Platinum jewelry now comes in a variety of alloys. Traditional Platinum jewelry is 95% pure platinum with 5% other metals. It’s stamped “PT 950″, “950 PT”, “PLAT”, or simply, “PT”. There have emerged some new manufacturing processes in recent years, one of which is 90%Platinum/10%Ruthenium. This is sometimes marked “90/10Pt/Ru”, “900Pt” or”Pt900″. Another composition goes by the brand name “Karat Platinum”. It is 58.5% platinum and 41.5% other metals, and is stamped “14ktPT”.

NEW METALS:
In the past couple of years, as Platinum has soared in price and people’s appetite for white metal jewelry has grown, some other metals have crossed over from consumer products to jewelry. Palladium, “PD950″, “950Palladium”, “950Pall”, or “950Pd”, is a less expensive metal in the Platinum family. Titanium “TI” is used for rings because of its light weight. Tungsten “Tungsten-carbide” is supposedly scratch-proof.

WHERE IS IT?
Finding a stamp is sometimes a challenge. You may need to use a magnifying glass or a loupe to see and read it.

Rings are always stamped on the inside of the shank. Earrings and pendants and other small items are stamped wherever a large enough surface is available. Sometimes earrings are stamped on the posts themselves. And chains are usually stamped on the ends - either on a small plate attached to the chain or on one of the endpieces. Clasps are also stamped, but because they can be replaced, the clasp’s composition doesn’t always tell you the chain’s composition.

People frequently ask what is the best way to clean their precious jewelry items.
There is no special secret to it. Rather, there are several tried-and-true methods of keeping things clean.

Most jewelry retailers offer special cloths or packaged jewelry cleaner that work just fine, and it’s a relatively inexpensive way of keeping things looking good.

In many instances, you can get just-as-good cleaning results from a simple soap and water solution.
Using a non-food bowl, place your jewelry in warm water and a little dish soap. Scrub with a soft toothbrush to remove any dirt and grime. (just remember not to use the toothbrush for anything else afterward!)
Most precious and semi-precious gemstones will tolerate this without any negative effects.

A fun cleaning method for silver is to place aluminum foil in a bowl, then fill with hot water, baking soda, and a little salt. Let your silver pieces sit in the solution for a few minutes, and the tarnish will be gone.

Pearl strands are a different case.
Because pearls are typically strung on thread, you don’t want to get them wet. If your pearls look dirty enough that you want to clean them, you should send them to a reputable pearl restringer. They can clean your pearls and provide new string at the same time, returning to you a strand that’s as good as new.
Talk to your local jeweler about having this done.

Of course, the best way to keep your jewelry free of tarnish and dirt is to store it in a clean, dry jewelry box. But that’s not really what jewelry is designed for.
Jewelry is made to be worn! So, wear it confidently.