- It will not rust, tarnish or corrode.
- Is the most malleable of any metal. It can be hammered so thin to be almost transparent. An ounce of pure gold can be hammered out to make a 300 square foot sheet.
- Can be drawn into wire finer than a human hair.
- Is very soft and easily workable.
- Has good bonding properties with other metals.
- Is biologically inactive, and has been used for dental work and other medical applications.
- Is highly reflective and is used for shielding for outer space equipment.
Gold's applications have touched every part of our lives. Telephones, televisions, computers, medical treatments are just a few examples of the uses of gold. But mention gold, and two things are usually thought of : coins and jewelry.
The value and beauty of the metal are the two attributes that make it a metal for coins. Jewelry also uses these attributes along with other characteristics of the metal. Malleability, ductility, non-tarnishing attributes and gold's ability to bond with other metals also make it one of the preferred metals for fine jewelry.
The fineness, or purity of gold is determined by the karat system. The karat system used for gold differs from the carat system used for diamonds in that diamond carats represents actual weight of the diamond, while gold karats represent the proportion of gold in the item by weight. The following gives karat designations and the percent of gold in each:
10k = 47.3%
12k = 50.00%
14k = 58.33%
18k = 75.00%
22k = 91.67%
24k = 99.99%
Some gold coins can be 24k, but because of the softness of the metal they are more likely to be 21k or 22k, or lower. For jewelry, 21k is the highest purity level for practical use, as anything more than that is too soft.
Alloys of gold used for jewelry contain other metals such as silver, copper, nickel, zinc, and others:
* Yellow Gold is an alloy of silver, copper or zinc and pure gold.
* White Gold is an alloy of white metals like silver, palladium and pure gold. It is usually plated with Rhodium to give it a more pure white color.
* Rose Gold is a gold alloy containing only copper and gold.
* Green Gold is an alloy containing only silver and gold.
* Black Hills Gold is an alloy combining copper, silver and gold.
10k gold is the least amount found in jewelry in the United States and most of the world. The higher the karat, the more expensive the jewelry. From the ancients to the moderns, gold still is the most beautiful and precious of metals.