Aventurine is a form of
quartz, characterised by its translucency and the presence of platy mineralinclusions that give a shimmering or glistening effect termed " aventurescence".
The most common colour of aventurine is green, but it may also be orange, brown, yellow, blue, or gray. Chrome-bearing
fuchsite(a variety of muscovite mica) is the classic inclusion, and gives a silvery green or blue sheen. Oranges and browns are attributed to hematiteor goethite. Because aventurine is a rock, its physical properties vary: its specific gravitymay lie between 2.64-2.69 and its hardness is somewhat lower than single-crystal quartzat around 6.5.
Aventurine feldspar or
sunstonecan be confused with orange and red aventurine quartzite, although the former is generally of a higher transparency. Aventurine is often banded and an overabundance of fuchsite may render it opaque, in which case it may be mistaken for malachiteat first glance.
The name "aventurine" derives from the Italian "a ventura" meaning "to cometh". This is an allusion to the lucky discovery of aventurine glass or goldstone at some point in the 18th century. Although it was known first, goldstone is now a common imitation of aventurine and sunstone. Goldstone is distinguished visually from the latter two minerals by its coarse flecks of
copper, dispersed within the glass in an unnaturally uniform manner. It is usually a golden brown, but may also be found in blue or green.
The majority of green and blue-green aventurine originates in
India(particularly in the vicinity of Mysoreand Madras) where it is employed by prolific artisans. Creamy white, gray and orange material is found in Chile, Spainand Russia. Most material is carved into beads and figurines with only the finer examples fashioned into cabochons, later being set into jewellery.
Main markets for aventurine are landscape stone, building stone, aquaria, monuments, and jewellery.
List of minerals
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