Opal

Opal. One of my favourite gems. The source of opals was dominated by Australia, until large deposits were found in Ethiopia. Australian suppliers tried to say that the Ethiopian were of inferior quality... but this has not proven to be correct. Indeed, I prefer Ethiopian opals.... and they are still considerably cheaper. Opal is a hydrated amorphous form of silica, and the water content can vary from 5 to 20%! because of its ability to absorb water, the cwt can change from week to week. Also, they should not be used when washing dishes, etc...as they can absorb impurities ( damn good excuse not to do them! :-)  They also have to be treated with more care than some other gems as they are only 5.5 to 6 on the moh's scale and can scratch easier than some gems. But. Their beauty makes the care worthwhile!

Opal wholesales to the trade today for approx. $20 for a 1 cwt stone of very low grade quality to approx. $1,000 for  a one carat example of extra fine quality. Black opals can go for $10,000 per carat.... but beware of smoke treated which look similar. The retail price will be several times that, depending on the retailers markup.