Gold is used on a massive scale for both coin minting and industrial purposes of course, as well as for decorative accents, dental needs and gold jewelry. Still, few people are truly informed about the hard numbers behind terms like 24 or 18 karat gold. In fact, to this day there is a world-wide debate on whether or not gold purity is measured in “carats” or “karats”! For the purpose of this article we shall refer to unit of purity measure as the later karat, that being the North American standard usage.

How it is to be utilized usually determines the karat count, or amount of gold in proportion to other metals which may be present. The higher the karat count, up to a count of 24, the more pure the gold. Gold is often alloyed, or combined in the smelting process, with other metals to increase its hardness and durability or to meet the needs of those who may have an allergy. The amount of hardness required is determined by the intended use for the gold. Jewelry, for example, gets a lot more handling than coins or bars and so is often alloyed with harder metals such as silver, copper and sometimes nickel. In custom or other high-end jewelry making, platinum is more than not the preferred choice for alloying gold with.

The composition of alloys used in jewelry in most countries is denoted in the ‘Karat System’. Unlike carat counts for gemstones, which measure weight, when counting karats for gold it needs to be understood that purity is the metric of measure. Gold is often times measured in more scientific terms by parts per thousand. Hence, 999 and 990 parts per thousand gold bars (the other parts being another metal such as silver or platinum for example). This is metric is rarely is ever used by jewelers and wedding ring retailers, they preferring the more widely known standard of measured. However, should your jeweler ever refer to the “fineness” of the gold in the ring you are considering purchasing, then they are referring to the parts per thousand ratio; not how lovely it is!

Let’s quickly examine how the Karat System is broken down in the jewelry industry. Twenty-four carat gold is pure gold with nothing added. This is the purest gold available. It has a fineness of 1000. Sometimes this is expressed as 999 fine as opposed to being an even 1000. This is because it is very difficult to get pure gold with absolutely no impurities such as trace carbon or lead elements, and possibly it is for legal reasons as well. This applies to gold coins more so than fine jewelry. Canadian Maples, US Gold Eagles and South African Krugerrands are all metered as 99.999% pure gold. How does this relate to Karat purity?

22 carat is 916.6 fine gold
18 carat is 750 fine gold
14 carat is 585 fine gold
9 carat is 375 fine gold

There are other accepted purity standards available as well as those above, but these are the most common. This tells you how much gold there is in any wedding or engagement ring you may be considering purchasing. Fourteen carat, for example, is 585 parts gold to 415 parts other metal. The other alloyed metal goes a long way in determining the final price of the ring, as platinum is much more expensive than say silver.

Tags: alloy, band, carat, fine, fineness, gold, karat, purity, ring, wedding

This entry was posted on Wednesday, April 22nd, 2009 at 5:53 pm and is filed under Gold Wedding Rings. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.