Mexican Opal

Mexican Opal


The birthstone of Oktober is an absolutely beautiful multicolored gemstone, that many people love. This national gemstone of Australia has many facets, great ones, and lesser features. In this blog post, I explain why your love for the opal can be brittle. And what you can do about it.

The opal can be brittle

Opal is a form of silica and when the silica was liquefied by vulcanism and high pressure it was washed down in the fissures of the surrounding rock. When the temperature cooled down the silica hardened and that stuff is what we call ‘opal’ now. So opal is not a crystal, but an amorphous solid material, that can contain between 3 and 21% water (weight). Some opal is formed in volcanic rock, like in Mexico or in sedimentary rock, like in Australia.

Opal does not last for ages. Since opal contains for a part of water, that water dries out during the time. And that opal will get brittle, gets softer and little cracks occur. That structure diffracts light and that is the reason that opal has such a lot of different colors in the gemstone, like white, black, olive, pink, rose, magenta, yellow, orange.

The opal is a very delicate and soft gemstone (5.5 to 6.5 on Moh’s scale) and most of the time it is milky and translucent. But the best quality opal gemstone is transparent. Actually, opal is somewhat porous. This means that you should not put an opal in another liquid than water. And opal can crack easily when it is dryed out too rapidly after mining.

The opal was not popular with jewelry makers

The jewelers did not like the opal very much, They did not know how to handle the gemstone or how to cut it properly. And when the opal dried out the gemstone could break during the cutting or polishing process. And that meant bad luck for the jeweler.

With the modern methods and good professional workmanship nowadays the opal is hard to work with, but not impossible. And since the gemstone is so beautiful, a lot of jewelry makers and designers go for it and they get great results.

Australian opal

Australian Opal

Opal, a great and beautiful gemstone.

The opal is easily recognized because of its iridescent colors, like a little rainbow but then all colors together in one stone. That play of color comes from the little silica plates in the gemstone that breaks the light. The more briljant the color the higher the price for the opal.

All opals have another color range, some have more red and orange, others are more green or blue. Black opals have all the colors. Speaking about the price… opals with more red are the rarest and the most expensive. The green and blue ones are more found and therefore cheaper.

How to take care of your opals the best?

  • Opal is a soft gemstone and that means that you can scratch or bump the stone easily. So take good care of them. Never ever put any oil or another chemical on your opals, only maybe water.
  • Keep your opal in a rather humid surrounding so that they don’t dry out or crack. So put your opal in water for a few hours now and then. And when you have a piece of jewelry of opal and other gemstones leave your jewelry in the bathroom: not in the water but in the humid surroundings.

The opal can be brittle when it is getting dried out, but your love for the opal will never get brittle, it will strengthen the stone. So take good care of it and your opal will last a long time.

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