Diamonds are still a girl's best friend, right? We love the shiny gems. They are the most popular rocks sold today. But what exactly are they, anyway? Where do they come from? What else are they used for?

Diamonds are a mineral in one of the two crystalline forms\rof the element carbon. They are the hardest natural\rsubstance man knows. Diamonds are sold as gems, and \rused\rin industrial applications for smoothing, cutting, and\rpolishing hard materials.

Diamonds are most famous for crystallizing in the common\rcolorless form. They may also be tranlucent to transparent\rwhite, yellow, green, blue, or brown. Diamonds have a high\rrefractive index which is why they are so brilliant and\rsparkly after cutting. The familiar shape of the diamond is\rthe octahedron.

The most brilliant diamonds become gemstones for jewelry \rand\rother uses. For those that don't make it to gems, there\rare other options. There is bort, which is a more poorly\rcrystallized or undesirable color and in fragmentary\rcondition, and carbonados which is gray to black opaque.\rBort and carbonados are used as abrasives for the cutting \rof\rdiamonds and the cutting heads of industrial rock drills.

Diamonds are found in alluvial formations and in volcanic\rpipes, filled for most of their length with blue ground or\rkimberlite, and igneous rock consisting primarily of\rserpentine. Diamond yielding earth is mined by both the\ropen-pit method and by underground mining. After removal \rto\rthe surface, the soil is crushed and concentrated. Passing\rthe concentrated material in a stream of water over greased\rtables does the needed sorting. The diamond is largely \rwater\rrepellent and sticks to the grease and the other minerals\rretain a film of water, which prevents the sticking to\rthe grease. Then the diamonds are removed from the \rgrease,\rcleaned, and graded for sale and use.

The earliest sources of gem diamonds were India and \rBorneo.\rSome famous diamonds are the Great Mogul, Regent, and \rPitt.\rOther famous diamonds include the Hope (blue), Dresden\r(green) and Tiffany (yellow). In the early 18th century,\rdeposits similar to those in India were found in Brazil,\rmainly of carbonados. In 1867 a stone found in South Africa\rwas recognized as a diamond. Within a few years began a \rwild\rsearch for diamonds. In 1870-1871, dry diggings including\rmost of the celebrated mines were discovered.

Synthetic diamonds were successfully produced in 1955; a\rnumber of small crystals were produced when pure\rgraphite mixed with a catalyst was subjected to pressure of\rabout 1 million lb per sq in. and temperature of the order\rof 5,000-F (3,000-C). Synthetic diamonds now are \rextensively\rused for industry, mainly due to the ease of obtaining and\rlower cost for them. Diamonds are still very popular and\rsymbolize many things. Their popularity does not seem to \rbe\rdwindling any time in the near future.

The author became fascinated with diamonds from an early \rage. She has studied diamonds and their various uses. \rWithout diamonds, many products that we enjoy and use on \ra daily basis would not exist.

She consults with various industries worldwide to help them \rto understand diamonds uses in their manufacturing \rprocesses.

Charmaine Stought is enthusiastic about diamonds and \ris the originator of FEEL Diamonds