is the name for the mineral species that is number 8
on Mohs’ scale of hardness. There is some uncertainty
regarding the name. Some say it comes from the Sanskrit
word meaning “fire.” Others link it to the
Red Sea Island of Topazios (Zabargad or St. John’s
Island), where peridot has been found.
For the general public, topaz means a yellow gem, and
much citrine and smoky quartz has been sold as “golden
topaz” and “smoky topaz.” The terms
“imperial” and “precious” topaz
are often used to distinguish between true topaz and
the quartz look-alikes.
The name “imperial topaz” is said to have
originated in the 19th century in Russia, where the
Ural Mountain mines were an important source. According
to some sources, pink topaz from those mines was restricted
to the family of the Czar. Today, the gem trade generally
uses the term for pink, orange and red topaz, which
comes mainly from Ouro Prêto, Brazil. Fine pink
topaz also comes from the Katlang area of Pakistan.
Topaz commonly occurs in colorless
and brown colors, it is the rare golden, orange, pink,
red and purple colors, which are often termed “precious”
or “imperial” topaz, that are the mainstay
of the fine gem market. While blue topaz is found in
nature, most of the material is produced by a combination
Yellow and brown topaz owe their color to color centers.
The impurity chromium produces pink to red colors. A
combination of color centers and chromium produces orange
topaz. Blue topaz is colored by color centers.
that the color of some brown topaz may fade with time.
Due to its orange to red-orange color,
topaz generally looks best under incandescent light.
In contrast, blue topaz looks best under daylight or
fluorescent light. When buying any gem, it is always
a good idea to examine it under a variety of light sources,
to eliminate future surprises.
Topaz from most sources is reasonably
clean. Thus eye-clean stones are both desirable and
possible. The exception is with pink and red topaz,
where only small stones are normally available. In those
colors, a slightly higher degree of inclusions are tolerated.
Due to the shape of the rough (elongated
prisms), topaz is generally cut as elongated stones,
typically emerald cuts, elongated ovals, cushions and
pears. To save weight, pears in particular are often
cut with overly narrow shoulders. Due to the huge production,
blue topaz is cut in virtually any shape and style one
can imagine. Cabochon-cut topazes are rarely seen.
While topaz does have a perfect basal cleavage, it is
not an easy cleavage, and so does not present too much
difficulty to the cutter. Nevertheless, cutters will
often try to ensure that no facet is parallel to the
cleavage direction and jewelers try to mount valuable
stones in settings that protect the stone.
Topaz sometimes occurs in enormous
sizes, where clean gems of even 1000 cts. are known.
Indeed, faceted stones of tens of thousands of carats
have been produced from some monster crystals. However,
cut stones of the prized “imperial” colors
(orange, pink and red) are more rare. Fine pinks and
reds above 5 cts. are scarce. Fine oranges above 20
cts. are also rare.
Gem topaz has been found at a number
of localities around the world, including Brazil, Nigeria,
Sri Lanka, Russia, Burma, Pakistan, USA and Mexico.
The premier source is near Ouro Prêto in Brazil’s
Minas Gerais state.
has the following composition: Al2(F,OH)2SiO4
Perfect (but not that easy) basal
3.53 ± 0.04
Orthorhombic; usually occurs
as vertically striated elongated prisms topped
Orange, yellow, brown, blue,
pink, colorless, rarely red
Weak to moderate, dichroic
Ultrasonic: not safe; never clean
Steamer: not safe
The best way to care for topaz is to clean it
with warm, soapy water. Avoid exposure to heat,
acids and rapid temperature changes. Strong heat
may alter or destroy color.
Most blue topaz is made by irradiation and then
heat; this treatment is undetectable and extremely
Blue topaz irradiated with in nuclear reactors
can emit dangerous levels of radiation; it must
be allowed to cool down to safe levels before
Some orangy topaz is heated to destroy the color
centers, leaving behind the chromium-caused pink