BLUE TOPAZ GEMSTONE
Blue Topaz is the second most popular blue coloured gemstones and is used widely in the making of classic jewellery pieces. It scores 8 on Moh's scale (which is not bad at all) and can be used to develop variety of necklaces, bracelets and other jewellery items. This gemstone works beautifully among blue coloured gemstone lovers and has very exciting dressing up option to offer to aficionados.
Blue topaz is basically the irradiated form of natural topaz where the stone is irradiated with gamma rays in a cobalt chamber- a practice that has got many brows raised in US and gave fatal blow to the sales of this topaz due to quarantine troubles. Another way of achieving the blue topaz of Swiss Blue variety is reacting it with electrons in an accelerometer. This treatment was named as 'linac treatment' and helped the makers get sky blue colour which is actually very appealing option for making artistic fashion jewellery.
The best blue hue is achieved when the stone is made further deep blue and variety is known as 'London Blue Topaz' that actually is an affordable alternative to very pricey Blue Sapphire.
Blue Topaz, since all these are treated with radioactive substances, are required to wait in secured chambers before declaring them ready to use. It is said that linearly accelerated blue topaz can be used after few weeks while those treated in nuclear reactors are usable only after few years. Since there were no techniques available to detect the radioactivity in a said blue topaz crystal, all were required to pass the NRC (Nuclear Regulatory Commission), USA accreditation test something that jewellers found very time-consuming. This requirement forced the jewellers to take Blue Topaz off the shelves and thus the gemstone lost its popularity since 1997.
Blue Topaz, though very hard, tends to break into pieces very easily when struck hard as it exhibits very definite cleavage. Therefore, it is not so durable as other gemstones like diamond, ruby and sapphire that stand just one podium up on Moh's hardness scale.
Topaz is certainly a very affordable gemstone because of its abundance in various regions across the world. Blue topaz can be made only by the radiation process and the sight of a natural blue topaz is worth making headlines due to rarity exhibited.
Lapis, Kyanite, Fluorite and Iolite are some of the same coloured gemstones that are way too cheaper than blue topaz. But none of these score as high on ornamental value as blue topaz because of unwanted softness.