October Birthstones: Opal & Tourmaline
Posted on September 10 2015
October has two birthstones: Opal and Tourmaline
Opals are famous for their “play of colors” – many stones flash the colors of the rainbow when moved, due to the interference of light on small cracks and other internal structural differences. Opals also have characteristic colors due to impurities within the stone. The milky or pearly appearance of some opals are due to inclusions of tiny gas bubbles. Yellows and reds from iron oxides.
The principal source of opals is Australia, noted for its magnificent black opals. Fire opals were first mined in Mexico, and continue to be produced today. In the United States, brilliant fire opals are also found in Nevada. Other commercial sources of opal are Brazil, Honduras, Nicaragua, Guatemala, Japan and Ireland.
The name opal is derived from the Sanskrit word “upala,” as well as the Latin “opalus,” meaning “precious stone.”
Here are a few Australian Opal pieces available on my website.
The alternate birthstone for October is the tourmaline, a gemstone that exhibits the broadest spectrum of gemstone colors.
Gem-quality forms of this mineral have in the past been misidentified as rubies, emeralds and sapphires. In fact, a famous tourmaline-the size of a pigeon’s egg-belonging to the Russian Empress Catherine the Great was long thought to be a ruby. The name of this gemstone is believed to derive from the Singhalese (Sri Lankan) word “toramalli,” a term applied to yellow, green or brown stones, that means “something little out of the earth.”
Most tourmalines are found in a myriad of colors: yellow, green, red, blue, pink, brown, black. Some even have bi-colored properties. A valued bi-colored variety of tourmaline, found in Brazil, is called the “watermelon.” The outer edges of the gem are green, transitioning to a transparent white zone that gives way to a pink or light red interior. Paraiba tourmaline is the rarest tourmaline and the only one that contains the color blue. Found in Paraiba, Brazil, it ranges in color from blue to pink to green.
Here are some tourmaline pieces of jewelry currently on my website: