Wednesday, 26 May 2010

Unlucky for some

Opals have a reputation for being unlucky, and there are various possible reasons floating around the internet it turns out. The most plausible is the negative press the stone got from Sir Walter Scott's novel 'Anne of Geierstein'. I'd never heard of it. Apparently somebody dies after their opal gets wet and turns colourless. Prior to the book, opals were considered very lucky. Power of the press.

Lucky or unlucky, opal can be a beautiful stone. Like jet, it's another stone saddled with the unfortunate designation of mineraloid, because it's essentially hydrated quartz. The water content varies up to between 15-20%, and this will affect the stability of what can be a temperamental stone. There's quite a range - milk, jelly, fire, boulder, cherry - but when most people think of opal it's of the precious gemstone types. The vivid flashes of colour that can be seen in some varieties is due to the way the quartz is arranged in its construction. Tiny spheres of quartz are packed together in grids and this structure will diffract light passing through to create a play of colour.

It's a bit of a pain to work as a gemstone - it's prone to cracking and usually the best display face will require careful positioning. Like with most gemstones now, there are a few synthetic forms available now. Gilson opal was the first effective one, developed in the 70s, but I saw some Japanese stuff a couple of years ago that looked amazing. Expensive, but amazing. The bit shown above is from Welo in Ethiopia. The material has been around for a few years, but I've thought it a little too expensive for me to find a market for. Last year, though, a new site was found, there were a bunch of new sellers around and the price was very good. I bought a load and I'll get some more this year.

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