(Continuing with my infomercial... )
Gold is a wonderful metal. It is malleable and ductile but durable, and does not oxidize or tarnish. It has been treasured though out history. Evidence of its use goes back as far as 6000 B.C. It was used in the first coinage between 643 and 630 B.C. It is an emblem of wealth, and a supporter of the financial system for years. The U.S. did not go off the Gold Standard until 1971. The Gold Standard based currency on a fixed retrievable amount of gold. Investors still buy gold seeking security or financial gain.
Gold is measured in troy ounces, 1 troy ounce being 31.1 grams. Because gold is a soft metal it is alloyed with other metals to harden it and make it more durable. The purity of gold is measured in karats, which is an ancient Middle Eastern unit of weight derived from the carob seed. 24 karats (or carats) is pure gold. 14 karats is the most common (particularly for rings) and has 58.3% gold mixed with other metals usually silver and copper. Different colored gold can be achieved with the other metals that are mixed with it. The karat designation applies to the amount of gold only. With white gold, nickel or palladium is used. With red gold, copper. Blue gold has iron in it (which makes it more brittle.) Any piece of jewelry should be stamped stating its gold content, and if there is a question a jeweler can test the metal.
About 78% of gold used each year is used in jewelry. The industrial uses include rhuematoid arthritis treatment, dentistry, electronics, and computers.
Gold is a joy to work with for the jeweler. 1064.43 °C is the melting point making it far more accessible than platinum. It is easily soldered and fabricated, but retains that luster that has made it so attractive and sought after through the ages.
Below is a clip that I found on youtube about gold. Warning: its a downer! When the Zimbabwean says a tin of grain for 1 gram of gold, that's 30 bucks! Way too much for the hungry! *And I went on youtube looking for the sound of one hand clapping...*
*the embed was disabled.*