October's Birthstones

There are two birthstones which represent October. One is opal and the other, tourmaline.

The name opal is derived from the Latin word "opalus" which means "precious stone. Pliny described an opal as though it was made up of all the glorious gemstones in union with each other.

Opals are famous for their beautiful array of colours. Many stones flash all of the colours of the rainbow when moved, due to the interference of light on small cracks and other internal structural differences. Impurities within the stone can also add colour to opals. Microscopic gas bubbles within the gem can add a pearly appearance. Trace amounts of iron oxides will give the stone a yellowish or red look. There are also highly prized "black" opals which flash green, red, blue and violet in light, these having magnesium oxides in them. Probably the most valuable is the "harlequin opal," which displays splinters of red, yellow and green.

Opal is composed of silicon dioxide, like quartz, but contains up to ten percent water and is softer. It can be easily altered in appearance by use of heat and pressure. The differing amounts of water determine appearance. If water evaporates out of opal, the gemstone will shrink in size and often cracks appear from the stress. Most opals come from Australia but they are also found in Mexico and Nevada and Ireland.

Ancient Romans believed the opal was a symbol of love and hope. Chinese referred to the gem as the "anchor of hope." Arabs believe opal fell from the heavens in flashes of lightning. A widespread belief of the powers of opal is that it renders the wearer invisible, so it was no doubt a popular stone of thieves!

In Medieval Europe, opals could indicate the health of it's wearer. It was believed that the stone would change in intensity if the wearer became ill. It was also thought that the opal could strengthen the heart, guard against infection and prevent swooning. This all changed however when the black death swept across Europe in the 1400's, and one quarter of the population died. The opal was believed to be the cause of death. It was said the opal would stay brilliant until the person died, then lose it's lustre. There is some truth in that the stone is sensitive to body temperature, and indeed loses intensity as the body changed from fever to cold death!

In Elizabethan England, Shakespeare wrote of it in the Twelfth Night as the "queen of gems." Queen Victoria presented her children with opal jewelry, thus making the the stone popular.

In Australia, there is a legend of a huge opal that governs the stars and guides human love, as well as controls the gold in mines. But Australian aborigines see it in a different light -- to them, the opal is the devil that lurks in the ground, a half-serpent and half-human with flashes of wicked magic that lures men to destruction.

Tourmaline is the other October birthstone. Of all the minerals, tourmaline exhibits the broadest range of colours. Tourmaline has even been mistaken for rubies and emeralds! A famous tourmaline the size of an egg and belonging to Catherine the Great was long thought to be a ruby.

Tourmaline is a hard glassy mineral in hues of black, white, blue, green, red, pink, brown and colourless. The colours are opaque to transparent. The composition of tourmaline is a complex mixture of compounds of sodium, calcium, magnesium, lithium, aluminum and iron. Crystals as large as one meter have been found. Small amounts of manganese produces a pink colour, while ferrous iron, chromium or vanadium will produce a green gemstone.

Tourmaline has a unique property in that if it is warmed or rubbed it will become charged with static electricity and will attract bits of paper and lint. Ben Franklin used a piece of tourmaline when he studied electricity.

Tourmaline does not have much for myth and lore associated to it because it is discovered that long ago compared to other gems. It has however, often been referred to as the "peace stone" because it is believed to dispel fear and bring calm to its' wearer.

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