Harlequin OpalIn a recent post I was discussing the poetic traditional nomenclature in the gem world
Harlequin OpalIn a recent post I was discussing the poetic traditional nomenclature in the gem world in relation to yellow diamonds (see http://bit.ly/2rGyVZM) but the opal world is also filled with such names albeit of more recent origin than the traditional Old World ones which in some cases date back into antiquity. Named after the traditional costume of a carnival jester character depicted in the second photo (originally from a 16th century CE opera but probably itself rooted in something older), it is the rarest and most highly valued pattern in amorphous gem silica in the gem market. Many stones only have one small sector with it so a beauty like this piece from Australia (size not available) is a genuine find. It is defined as a repeating pattern of diamonds or elongated squares, in this case picked out in play of colour. In practice many patterns are referred to in this way, some being a hopeful interpretation, others being repeating patterns of roughly the same size, but not diamonds or squares.The shifting hues are due to the fact that the silica spheres making up the opal are the right size and spacing to diffract the light into its component hues, and the most valued opals are those which display the full range of colours, from red to violet. Many less valued stones only display one or two. Here of course we have the lot, making this piece truly beautiful. Most such stones come from Australia but occasional Ethiopian pieces display this pattern (along with a few cool unique ones of their own, see http://bit.ly/2Gqks7s, http://bit.ly/2nlsIgj, http://bit.ly/2DUQjPy, for some examples).LozImage credit: Opal Auctions 2: Chris Brownhttp://bit.ly/2BxguGLhttps://youtu.be/41G2KrLqGDUhttp://bit.ly/2DHkP02 -- source link
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