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Star diopside
Recently, diopside displaying asterism when
the stone cut en cabochon has been seen quite often on the
mark for minor gemstones.
Appearance This is generally a blackish or
blackis green color; rarely a definite green. It is, of course,
cut iw round or oval cabochons, which are generally biconvF
with a roughly shaped, unpolished base. The star chara teristically
has four rays, two of which are straight, whi the other two,
not at right angles to the first pair, loc. slightly wavy
(the crystal does not, in fact, have fourfo symmetry). Sometimes,
oriented acicular (needlelike) sw face crystalline inclusions
are clearly visible, especial from below.
Stones weighing several tens of carats are also found, bt.
they are not normally cut so large, as this makes them harto
use.
Distinctive features Star diopside has only
binary syr metry, and the star has four rays, rather than
six like othe star stones.
When the gem contains conspicuous needlelike crystal - (of
magnetite) it is easily attracted by a magnet.
Occurrence Star diopside comes
mainly from India. Value Very low, one of
the lowest for gems, even thougw asterism always has a certain
appeal.
Simulants and synthetics It is neither imitated
nor prcduced synthetically. It is sometimes passed off as
star sapphire, although the resemblance is highly superficial,
giver the obvious difference in asterism.
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