The most common color of aventurine is green, but it can also be orange, brown, yellow, blue, or grey. 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
hematite or
goethite. Because aventurine is a
rock, its physical properties vary: its
specific gravity may lie between 2.64–2.69 and its
hardness is somewhat lower than single-crystal quartz at around 6.5.
Aventurine feldspar or
sunstone can 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
malachite at first glance. The name
aventurine derives from the
Italian "
a ventura" meaning "by chance". This is an allusion to the lucky discovery of
aventurine glass or
goldstone at some point in the 18th century. One story is that this kind of glass was originally made accidentally at Murano by a workman, who let some copper filings fall into the molten "metal", whence the product was called
avventurino. From the Murano glass the name passed to the mineral, which displayed a rather similar appearance. 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
Mysore and
Chennai) where it is employed by prolific artisans. Creamy white, gray and orange material is found in
Chile,
Spain and
Russia. Most material is carved into beads and figurines with only the finer examples fashioned into
cabochons, later being set into
jewelry. == See also ==