Gold has been highly valued for many thousands of years, not only for its beauty but for its other remarkable qualities. It does not corrode; a gold coin which Gold Necklaceshas lain at the bottom of the ocean for hundreds of years will emerge with the brightness of a newly-minted coin. It is extraordinarily malleable; it can be worked into many forms, and a single ounce of gold can be pounded into a sheet of 100 square feet. It is ductile; one ounce can be drawn into a wire 50 miles in length. Because it does not corrode, it is eternal. The gold wedding ring you are wearing today can contain gold that was once in an ancient Greek coin, or an Egyptian pharaoh's crown.
The 'Nobility' of Gold
Gold played an important role in ancient civilizations on almost every continent and continues to be treasured to this day. What has made this beautiful sun-colored metal so desirable? Besides its aesthetically pleasing color, gold is malleable enough to be bent, twisted,hammered, heated, and otherwise worked into jewelry without cracking and breaking. A single ounce of gold can be drawn into a wire over 50 miles long! And gold is timeless, literally. It is one of the few metals classified as 'noble' (platinum is another). Noble metals do not oxidize. In other words, they do not corrode, rust, or tarnish (like silver, for example) when they come into contact with the atmosphere. This means that gold jewelry lasts for ages. Unbelievably, gold treasures have been recovered after centuries on the ocean floor still in essentially pristine condition.
Karats and Carats
The term 'karat' should not be confused with the term 'carat'. Carat is a unit of weight equivalent to one-fifth of a gram that is used in weighing gemstones. Karat refers to the percentage of gold in a given alloy. Because pure gold is too soft to be use in most jewelry, it is usually alloyed with other metals so that it will hold its shape better. The karatage of gold is determined by dividing the metal alloy into 24 parts. Pure gold contains 24 out of 24 parts (24/24) or 100% gold; 18K gold contains 18/24 or 75% gold; 14K contains 14/24 or 58.3% gold; and 10K gold contains 10/24 or 41.7% gold. European manufactures frequently use a system based on parts per 1000 where '750' is used for 18K, '585' for 14K and '417' for 10K. Alloys of less than 10K cannot be legally sold as gold in the United States.
Colors of Gold
The colors of gold are determined by the types and ratios of the various metals used in their alloys. Although there are a number of minor components, the primary alloy components for the different colors of gold are:
Trademarks and Hallmarks
In addition to the karat marking, also called the quality mark, federal law requires gold jewelry to be stamped with a trademark or hallmark. This identifies the manufacturer and sometimes the country of origin. Some Italian gold jewelry will also have marks identifying the region in which the item was produced. It is important that these marks are present on jewelry you are considering for purchase. Although they do not guarantee the quality and gold content of the piece, they do establish accountability, and their absence does imply that the item is not being marketed in accordance with federal law.
Care and Cleaning of Jewelry
While gold itself does not oxidize, the alloys used in karat gold can be susceptible to chlorine. This is especially true for white gold. Repeated exposure to chlorine can break down the structure of karat gold, so it is important to keep your jewelry out of swimming pools and jacuzzis and away from chlorinated cleaning products as much as possible. Cleaning your gold jewelry frequently, with a mild soap such as dishwashing liquid and a soft toothbrush, will go a long way in ensuring that it will have a long and enjoyable life. Gold is still a soft metal and should be stored accordingly. Keep it separated from other jewelry, especially diamond jewelry, in a separate container if possible. Herringbone and other delicate chains should be stored flat so they won't kink.
White Gold and Sapphire Ring