How to Recognize Hallmarks

What is a hallmark?

A hallmark is a marking on a piece of jewelry that guarantees a minimum percentage of gold, silver, platinum or palladium present in the item. When looking at your jewelry, if it is a gold, silver, platinum or palladium alloy then a hallmark will always be present, usually somewhere where it will not be visible when worn. This can be the inside face of a ring, inside a locket or on the clasp of a chain.

There are various different types of gold jewelry so you need to examine the hallmark carefully to determine the value of your jewelry. Major categories you will encounter are:

Karat gold
Gold filled
Gold plated
Vermeil

Karat Gold

What is a karat? Karat denotes the amount of gold by weight in an alloy, known as the fineness. One karat is 1/24th gold purity by weight, therefore pure or fine gold is known as 24 karat. The popular jewelry alloys in the U.S.A. are:

22 karat or 22/24ths by weight of gold (91.67% pure gold) marked as 22K or 22kt
18 karat or 18/24ths by weight of gold (75.00% pure gold) marked as 18K or 18kt
14 karat or 14/24ths by weight of gold (58.53% pure gold) marked as 14K or 14kt
10 karat or 10/24ths by weight of gold (41.67% pure gold) marked as 10K or 10kt

10 karat is the minimum recognized purity of an alloy to be called "gold" in the United States.

Jewelry manufactures in countries outside the United States, especially mainland Europe, may use a different system of purity marking. This is a measure of the weight of fine gold in the object in parts per thousand.

Hallmark Identification Chart

Gold Filled

Gold filled, gold overlay or rolled gold jewelry is not the same as karat gold jewelry. Gold filled jewelry is that which has a layer of karat gold, minimum 10K, bonded to another metal – usually but not necessarily a brass alloy. This is done to make less expensive jewelry and the gold content is always lower than the other less valuable metal it is bonded to.

Jewelry can be marked gold filled or GF or 14kt GF. If you see "GF" with your hallmark, it is not solid gold but a combination of gold and another less valuable metal.

Gold Plated

For an object to be marked gold plated it must be plated with a karat gold of minimum 10kt to a thickness of at least 0.5 microns, which is equivalent to about 20 millionths of an inch. This is thin! Marking can be the minimum thickness and the karat used, again 10kt minimum. Example: 5 microns 18kt GP

If you see "GP" with your hallmark it is not solid gold but a very thin layer of gold plated over a base metal.

Vermeil

An object may be described as vermeil when it consists of a karat gold layer bonded or plated to sterling silver. As is always the case, the karat gold must be at least 10kt and in the case of vermeil the coating must be a minimum of 2.5 microns. If the coating is not a karat gold, an object may still be marked vermeil provided the base metal coating is disclosed.

Silver

For an object to be marked as either solid silver or sterling silver, at least 92.5% of the objects total weight must be fine silver. The usual marks used are sterling or 925. In some cases objects may be marked ster or STR.

Coin silver is 90% pure silver.

Platinum

For an object to be called platinum it must contain at least 95% pure platinum. So if your jewelry has the words platinum, plat or pt then it contains a minimum of 95% pure platinum. Alloys containing less than 95% pure platinum but 85% pure platinum or above will be marked with the parts per thousand number as follows:

900Plat or 900Pt (contains 90% pure platinum)
850Plat or 850Pt (contains 85% pure platinum)

If an object contains less than 85% pure platinum it will still be marked with the platinum content in parts per thousand. If your platinum jewelry has a mark you do not recognize here, email us and we can tell you the pure platinum content.

So if your jewelry is marked plat it will contain a minimum of 95% pure platinum. If it is marked 900Plat it will contain a minimum of 90% pure platinum. If it is marked 750Plat, it will contain 75% pure platinum, regardless of any other marks present.

Palladium

There is no actual hallmarking laws regarding palladium in the U.S. at present, but jewelers will mark palladium jewelry in much the same way as platinum, except using the marks pall or Pd instead of plat or Pt.

GET STARTED NOW!

Customer Log-In

Create your account and fill out the Jewelry Processing Form.

When completing the form, you have the options to Ship the Items Yourself (the quickest method) or Request a FREE Refinity Kit be mailed to you.

Click here to read details about these SHIPPING OPTIONS.

Phone: 1-800-400-4430
Business Hours: Monday-Friday, 9-5 EST