Rubies have been sought by humans since prehistoric times. Their color --
blood red (ruby is Latin for red) to pale rose -- has made them prized
inclusions in jewelry and other human decorations. Rubies are a
transparent variety of the aluminum oxide mineral corundum. The gemstone's
color is due to very small and varying amounts of chromium. The most
valuable rubies are a deep red and are often cut to enhance color, even at
the expense of weight. For more than 500 years the world's finest rubies
have come from Myanmar (formerly Burma) where they are gleaned from
limestone gravels. Rubies are prominent in legend and myth with Biblical
references that dub it the most precious of stones. Hindus believed the
color was due to an inextinguishable fire that burned within -- a fire
that could even be used to boil water. In 1908, the first synthetic ruby
was made utilizing a flame-fusion process and ammonia alum and chrome alum.
In 1960, an artificial ruby, like the one in this picture, was used in the
first working laser. Interested in more good stuff on rubies and other
precious and not-so-precious gems? Try this page. You can even get
credit.
Photo credit: Jill Banfield, professor of geology and geophysics,
University of Wisconsin-Madison.
