What You Need to Know About Platinum Jewelry

Platinum Content and Platinum Marks

Platinum markings and hallmarks to determine if your jewelry is made of platinum.
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Platinum is a rare precious metal primarily used to create fine jewelry. Its heavy weight and durability make platinum a metal that will not wear away with constant use like gold. Platinum holds fine gemstones firmly in place for the life of the jewelry when used for prongs and other setting components.

Platinum's natural white luster provides a rich backdrop for diamonds and can even make diamonds appear whiter than they really are.

  It's a metal that's elegant when used all by itself to create a piece of jewelry, either a simple polished item or a design with engraved motifs. The metal also looks stunning when combined with contrasting touches of 18K yellow gold.

There's no question that there are many advantages to choosing platinum over white gold. But how can you determine if jewelry you already own is made of platinum? The easiest way to determine the metal used in your jewelry is by examining the hallmarks or markings. All modern platinum jewelry requires stamps indicating metal content. 

Platinum Marks

Jewelry can contain different percentages of pure platinum. The US Federal Trade Commission, FTC, publishes guidelines for acceptable marking standards for platinum jewelry sold in the US.

Platinum content is usually expressed as the amount of pure platinum the jewelry contains in parts per thousand. Think about it like this: you mix up a huge bucket of fruit tea that contains 1,000 ounces--900 hundred of the ounces are plain tea and 100 are fruit juice.

That makes the tea 900 parts per thousand of your mix. Another way to express that is to say that tea makes up ninety percent of the mix.

Here are some important platinum facts regarding content markings:

  • Jewelry that contains at least 950 parts per thousand of pure platinum may be marked or described as "Platinum". 
  • Jewelry that contains 850, 900 or 950 parts per thousand of pure platinum may be marked "Plat" or "Pt" if a number is used in front of the term to disclose the amount of pure platinum in the mix, such as :
    • "850 Plat" or "850 Pt", or
    • "950 Plat" or "950 Pt"
  • Jewelry that contains at least 950 parts per thousand of platinum group metals, with at least 500 parts per thousand of the total pure platinum, may be marked as platinum as long as the numbers of each metal are disclosed. For instance,
    • "600 Pt. 350 Ir." or 600 Plat. 350 Irid." for 600 parts pure platinum and 350 parts iridium
    • "550Pt. 350Pd. 50Ir." or "550Plat. 350Pall. 50Irid." for 550 parts pure platinum, 350 parts palladium and 50 parts iridum

The FTC is currently considering a request to allow manufacturers to mark jewelry as platinum even if it contains metals that are not part of the platinum group.

The Platinum Group of Metals

Acceptable alloys that are used with platinum are grouped together. These six related metals belong to the Platinum Group of Metals, or PGM:

  • Platinum
  • Iridium
  • Palladium
  • Ruthenium
  • Rhodium
  • Osmium

As long as 50% of the alloy contains platinum and some other combination of metals above, the piece can be labeled as containing platinum.

If for instance, jewelry contains 50% platinum and 50% gold, that piece can not contain a hallmark indicating the piece contains platinum. Also, you must include the alloy present in the mix if the piece contains less than 85% pure platinum. 

Ask your jeweler to explain platinum content and markings if you are not sure which combination is the most suitable for your jewelry purchase.

Edited by: Lauren Thomann