Origin of Opal
Since the ancient Roman times precious opal has been a very popular gemstone. This gemstone was included among all the other noble gems and interestingly it was given the second position after emeralds by the Romans. Most opal usually dates back to Cretaceous period over 60 million years old. The name of opal evolved from ‘Opalus’, a Roman word literally meaning ‘to see a change of colour’. As per other popular theories, the name of opal was derived from the term ‘Upala’, which is a Sanskrit word and it means a stone.
Appearance of Opal
Opals are notable with a mixture of pearly to milky opalescence and with a striking play of various colours. These vibrant colours flash and change when the stone is viewed from diverse directions and is caused by the interference of light along with minute cracks and other internal homogeneities. The precious opal is broadly used as a gemstone. Opal is fragile, heat sensitive and breaks and scratches easily.
Colours of Opal
Opal is basically colourless, but it is rare to found. Some dispersed impurities usually give the opal some really tedious body colours that vary from yellows and reds. Further, the various white and grey coloured Opals can be attributed to large quantity of minute gas-filled hollow space in them. The precious Opal depicts light with a magnificent play of some wonderful colours across the visible range, red being the most valued. Moreover, crystal opal has got a colourless backdrop and displays excellent play of colour, but, not like black or white Opal, it lets the light pass through it.
Varieties of Opal
Opal has hundred of diverse varieties which are used as insulation media, abrasives and ceramic ingredients. Fire Opal that is the reddish-yellow, orange, bright red or brownish-red body coloured type of Opal which is considered as the second most significant opal commercially. Black Opal is present with a very dark grey or blue to black body colour. This is particularly rare and highly prized. White Opal has light body colour and is much more common than black opal. Moreover, synthetic opal is also available widely and commercially. But the quality of the synthetic is not at par with natural Opal. It is rather low in thickness and mass and very permeable.
Benefits of Opal
Opals are also known to have several healing properties. In the medieval times, Opals were used to cure eye diseases. There is some healing ability, which varies according to the different types of Opals.
Opal is a mystifying gem, as each one appears different and has delicate beauty. It has always been one of the most popular gems of all times. It passes massive amounts of energy.