Pure gold is too soft for ordinary use and is hardened by alloying with silver, copper, and other metals. Gold and its many alloys are most often used in jewelry, coinage and as a standard for monetary exchange in many countries. Gold is measured in karats (k), when selling it in the form of jewlery. Pure gold being 24k, however, gold is more commonly sold in 20k, 18k, and 14k. The lower the "k," the more copper or silver that has been mixed into the gold. Gold is most commonly mixed with copper. Because of its high electrical conductivity and resistance to corrosion and other desirable combinations of physical and chemical properties, gold also emerged in the late 20th century as an essential industrial metal.
Gold Jewelry Buying Tips
Gold has always been treasured for its value, both as a metal and in the form of ornaments. We all buy gold for both of these reasons, directly or indirectly. If you’re buying gold as an investment, go for the purest form that you can buy. If buying simply for ornamentation, you may opt to choose a less pure form.
The purity of gold is displayed in karats: 10, 12, 18 and 24 karat gold. The number indicates purity. 18k gold is comprised of 18 parts of gold and 6 parts of other metals. 12K gold contains 12 parts of gold out of 24 and 10K gold would contain 12 parts of other metals. 24K gold is the purest and does not contain any other metal.
Gold jewelry uses gold of one or the other karats. Always ask about the purity of the gold used in the jewelry you buy. Very versatile, gold can be shaped into different forms: wires, flat sheets, rings or poured into a mold for custom shapes. This is why gold is widely used in jewelry.
If buying gold jewelry with stone insets like diamonds, rubies, emeralds or any other gemstones, always ask about the quality and purity of the stones used. The jeweler should be able to provide you with a certificate of authenticity of the gemstone, preferably from the GIA, Gemological Institute of America (http://www.gia.edu/) or the AGS American Gem Society (http://www.ags.org/).
You may have heard of White Gold. White gold is a gold alloy containing a percentage of nickel or platinum. Some people experience allergic reactions to white gold. Jewelers are now shifting to palladium as the other metal used in white gold since it does not create allergic reactions. Always ask for gold mixed with palladium when you buy white gold.
Avoid gold "plated" jewelry, unless you plan on infrequent use. Gold plating usually consists of a very fine layer of gold. The thinner the plating, the faster it will wear off and begin to look tarnished and worn out.