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Citrine quartz
Oddly enough, the basically yellow variety of
quartz is known as citrine quartz, or simply citrine, despite
the fact that generally the color is nothing like lemon yellow.
It was and still is called topaz or topaz quartz as well,
because o' a similarity in color, much to the detriment of
true topaz which is thus considered more plentiful, and less
valuable than by rights it should be.
Appearance The color varies
from pure yellow to dult yellow, honey, or brownish yellow,
sometimes even with a; russet tint. As with amethyst, the
color is often broken uF into patches or bands, although due
to its depth of hue, thc zoning is less obvious. It has good
luster (like amethyst and is generally very clear and virtually
free of inclusionbecause the amount of raw material available
allows for considerable selectivity. It is fashioned into
all the styles normal for transparent stones, except the brilliant
cut Large stones of 10 carats or even more are often seen
Distinctive features Color zoning, where present, m be an
aid to recognition. The density of citrine (togeth with that
of orthoclase) is the lowest for stones of this coi and is
much less than that of topaz, in particular. AlthouL normally
good, its luster is slightly inferior to that of topa: and
the latter can show signs of incipient cleavage, nev•
seen in citrine.
As with the majority of quartzes, the interference
figure characteristic, where this can be established. Citrine
is f: - less lustrous than yellow sapphire, which also normally
ha:highly characteristic inclusions. As a rule, however, citrir,
can only be distinguished from the numerous other yello:,
stones by an examination of the physical properties.
Occurrence Large quantities
of citrine are obtained fror Brazil. It is also found in the
United States (North Carolin; California), Spain, and the
Soviet Union.
Value Quite low, for a secondary
gem; less than that c amethyst. Like amethyst, it was much
more highly valued ir the past than it is today.
Simulants and synthetics It
is not imitated; but despitc its low value, it is synthesized,
like amethyst, on a IargE scale. The cost of the synthetic
version is equal to or only slightly lower than that of the
natural gemstone. Amethyst when heated, assumes the yellow
color of citrine.
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