Jeweller - November 2021

ORANGE & YELLOW
Colour Investigation
Brilliant transparent gemstones in warm tropical tones
of pale lemon, rich gold, delicate apricot or vivid saffron
can be challenging to identify. What could they be?
First in affordability and popularity is the quartz family
– from the delicate pastel tones of ‘lemon quartz’ to
the vibrant, vivid orange hues of citrine and all shades
in-between.
UNDERSTANDING GEMSTONE COLOUR
Sunset magic:
Orange & yellow gemstones
For centuries, orange and yellow gemstones have enraptured jewellers and jewellery-lovers,
with mystical properties attributed to their warm, sun-like glow, Jeweller discovers.
Citrine is commonly confused with a similarly-coloured
but more expensive topaz.
Natural citrine is the most valuable form of quartz, and
extremely rare. It occurs when amethyst formations are
close to natural heat sources in the Earth's crust.
It ranges in colour from a shade of light gold through to a
fiery reddened-yellow and owes its hue to traces of ferric iron.
The majority of citrine on the market, however, is actually
heat-treated purple amethyst.
This heat treatment – involving temperatures up to 560
degrees – helps replicate the yellow, gold and amber
shades of natural citrine and is clearly recognisable to a
trained professional by the subtle stripes that the process
leaves on the gem.stone
Heat-treated citrine is readily available, very affordable
and extremely durable.
The best specimens of natural citrine come from Brazil,
mined in Rio Grande do Sul. Other deposits include
Madagascar, the US, Spain and Africa.
Traditionally the darker shades have held more value but
recently consumer preference leans towards brighter
lemony hues.
Indeed, the name citrine is derived from the French word
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Legend says it acts as an energising stone against
issues of willpower, optimism, confidence and self-
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discipline.
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QUICK
FACTS
105t
estimated
weight of amber
produced from
Europe's forests
in the Paleogene
1556
year the term
citrine was first
used to describe
the gemstone
6.2kg
weight of the El
Dorado Topaz,
the world's
largest faceted
gemstone
citrin, meaning lemon-coloured. In this shade, citrine is
often confused with orange topaz.
There are few references in history to citrine, perhaps
because of the stone's rarity.
The first occurrences seem to be the use of citrine by
Romans for intaglio and cabochon in the centuries
immediately following the birth of Christ.
Citrine saw increased use as a gemstone in jewellery
during the Romantic Age (1837-1860).
Today, citrine is widely used in many jewellery styles.
The sunny gemstone’s beautiful colours can brighten
almost any jewellery style, although it goes particularly
well with yellow gold.
An inexpensive gem, citrine is the perfect stone for
popular free-form fancy cuts for unique and custommade
pieces.
Like all crystal quartzes, citrine has a hardness of 7 on
Mohs’ scale and is largely insensitive to scratches. It
will also withstand a few knocks, too, since its cleavage
properties are non-existent.
The gemstone’s durability makes it a suitable keepsake.
Indeed, citrine is the modern birthstone for November
and also the stone for the 13th year of marriage.
Like citrine, topaz is the birthstone of November. Yellow
topaz is often confused with citrine due to its similar colour.
Topaz is allochromatic, meaning it derives colour from
impurities and defects in its crystal structure; this
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