May 5, 2022

Topazes

Topazes are incredible stones which are willingly used by jewellers. Their hardness, which is 8 on the 10-point Mohs hardness scale ensures the durability of a polished gem. They come in many colours and are relatively easy to come across in nature. 


In nature, most topazes occur in pale colour variants - from almost colourless, slightly grey, and yellowish to brownish. They are not, however, not as sought after, as natural, intensely coloured specimens that are extremely rare and can reach very high prices. Imperial stones, which are orange-yellow gold, are the most valuable. So are the dark pink-red and the orange-red ones. The naturally intense blue topazes are equally desirable; however, those are extremely rare. 

In the 20th century, a method of obtaining the blue colour of topazes was developed. When subjected to light and heat treatment, the colourless, pale grey, pale yellow, and slightly blue topazes turned into gems of intense blue colour. 


This was how an alternative to the extremely rare and practically unobtainable blue topaz was created. A cheaper and commonly available version was introduced to the market. 

Because nearly all the blue topazes available on the market have gone through the above-described process. For that reason, it is essential to note that jewellery with blue topazes must not be exposed to strong sunlight and heat for too long. Otherwise, the artificially produced colour of the gem can return to its original state from before the dyeing process i.e. fade considerably.

JEWELLERY. MASTERPIECES OF ART OF 19TH AND 20TH CENTURY