Metal Alloys November 07 2013
Most gold that is used in jewelry is a gold alloy. An alloy is a substance composed of two or more metals. In the case of gold, in the US, it is denoted by karat. The karat refers to the amount of pure gold in it. 24k gold is pure gold, and is a extremely soft and malleable metal. For jewelry, gold is most commonly seen in 18k, 14k, and 10k alloys, where pure gold has been combined with other precious and non-precious metals (alloying). This alloying makes gold stronger, harder and more durable. It also is what gives gold its amazing range of colors. The carat denotes the amount of pure gold in the alloy. 10k gold contains 41.8% pure gold, 14k gold contains 58.5%, 18k contains 75.2%, and 22k contains 91.8% pure gold.
Pure gold is always a very rich yellow color. So when talking about colored gold, you are always talking about a gold alloy. It is the other metals that are mixed with the pure gold that give it it’s color.
14k rose, yellow and green gold are all made up of 58.5% pure gold, then the remainder of the alloy is silver, copper, and zinc. It is by varying the proportions of the silver and copper that you get the three different colors. Green gold contains more silver than yellow gold, and rose gold contains more copper than yellow gold.
Rose gold is a gold alloy that is similar in color to copper. This is due to its higher copper content. It is also referred to as red gold and pink gold. It is much more pink in color than 14k yellow gold, but a bit less pink than copper. Pure copper is not a good choice for a wedding band because it tarnishes very quickly, it is extremely soft, and will turn most people’s skin green. Which, is not harmful, just unsightly. 14k rose gold is a great option for someone wanting a copper colored wedding band.
The white metals that I typically work with are 10k, 14k and 18k white gold, 14k palladium white gold and 950 palladium. 14k white gold and 14k palladium white gold both contain 58.5% pure gold, but are alloyed with other metals to make them more white in color. 14k white gold contains gold, nickel, copper, and zinc. Whereas 14k palladium white gold contains gold, copper, silver, and palladium. 14k palladium white gold does not contain nickel, which is a metal allergen for a lot of people.
950 palladium is 95% pure palladium. Palladium is a metal in the platinum family, and shares many characteristics as platinum – durability, tarnish resistance, and is hypo-allergenic. It is a precious metal, and in addition to being used in jewelry, is has often been used in catalytic converters. It is a “white metal” that is slightly more gray than platinum or sterling silver. Palladium is much less expensive than platinum, but very durable.