I adore the ruby; it is one of my most favortie gemstones. It isn’t my birthstone no matter how much I wish otherwise. That doesn’t stop me from admiring the stone or dreaming of using it in some spactacularly (and outrageously) gorgeous piece of jewelry – for myself!

It is, however, the birthstone of those lucky people born in July so it is this month’s gemstone topic for this weblog.

Ruby red is both a color and an emotion. What do you think of when you see those words: ruby red…? I imagine the elegance of the early half of the last century, richly colored wine in crystal glasses, soft music and warm summer breezes and I feel the anticipation of a romantic adventure. Red is my favorite color!

The ruby itself has a long history of use both as a talisman and as an object of artful decoration. In ancient times it was variously thought to protect warriors in battle and others from general harm. It also had medicinal associations especially with respect to the blood. It is known to have been mined at least 2500 years ago.

Rubies, like their relations, the sapphires, are a variety of the second hardest mineral, corundum. In fact corundum of any color other than the reds is sapphire. As a jewelry component this aluminum oxide is often heat treated to improve the color and transparency. In its man made form it was an important component of early lasers. The red color is caused by some of the aluminum being replaced by chromium. If, however, all of the aluminum is replaced by chromium we then have a somewhat less hard mineral called eskolaite (which is, oddly enough, green in color). Besides lasers and jewelry, ruby has been used as an abrasive and polishing agent.

Here is an example of a highly polished ruby cabochon:

References
Ruby Mineral Information and Data, Mindat.org http://www.mindat.org/min-3473.html
Corundum Mineral, Uses and Properties Geology.com http://geology.com/minerals/corundum.shtml

This entry was posted on Tuesday, July 21st, 2009 at 9:49 PM and is filed under Good to Know. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.