General
information & images about the kinds of gemstones jeweler Lynn
Guenther uses in her jewelry. The images are provided to
show general color of the gemstones, and are not images of
actual gemstones used by Lynn. For more in depth information,
use the Wikipedia links provided with each gemstone description.
Amethyst
is a violet variety of
quartz often used in
jewelry. The name comes from the
Ancient Greek a- ("not") and methustos
("intoxicated"), a reference to the belief that the stone
protected its owner from drunkenness; the ancient Greeks and
Romans wore amethyst and made drinking vessels of it in the
belief that it would prevent intoxication.
Wikipedia Information about Amethyst
Blue
Topaz is
a
silicate mineral
of aluminum and fluorine with the chemical formula Al2SiO4(F,OH)2.
Topaz crystallizes in the
orthorhombic
system and its
crystals
are mostly prismatic terminated by pyramidal and other faces.
Pure topaz
is colorless and transparent but is usually
tinted by impurities; typical topaz is wine,
yellow, pale gray or reddish-orange, blue brown.
It can also be made white, pale green, blue,
gold, pink (rare), reddish-yellow or opaque to
transparent/translucent.
Wikipedia Information
about Topaz
Citrine
is a variety of quartz whose color ranges from a pale yellow to
brown. It is nearly impossible to tell cut citrine from yellow
topaz visibly. Citrine has
ferric impurities, and is rarely found
naturally. Most commercial citrine is in fact artificially
heated
amethyst or
smoky quartz. Brazil is the leading
producer of citrine, with much of its production coming from the
state of Rio Grande do Sul.
Citrine is one of three
traditional
birthstones for the month of November.
Wikipedia Information about Citrines
Emeralds
are a variety of the
mineral
beryl (Be3Al2(SiO3)6,)
colored green by trace amounts of
chromium and sometimes
vanadium. Beryl has a hardness of 7.5
- 8 on the 10 point
Mohs
scale of mineral hardness.
Most emeralds are highly
included, so their toughness
(resistance to breakage) is classified as generally poor. The
word "emerald" comes from Latin smaragdus, via Greek
smaragdos, its original source being a Semitic word izmargad or the Sanskrit word,
marakata, meaning
"emerald" or "green".
Wikipedia Information about Emeralds
Garnet
includes a group of minerals that
have been used since the Bronze Age as
gemstones
and abrasives. The
name "garnet" may come from either the Middle
English word gernet meaning 'dark red',
or the Latin granatus ("grain"), possibly
a reference to the Punica granatum
("pomegranate"), a plant with red seeds similar
in shape, size, and color to some garnet
crystals.
Wikipedia Information
about Garnets
Iolite
(also known as
Cordierite) As the transparent variety iolite, it is often used
as a gemstone. The name "iolite" comes from the Greek word for
violet. Another old name is dichroite, a Greek word
meaning "two-colored rock", a reference to cordierite's strong
pleochroism. It has also been called "water-sapphire" and
"Vikings' Compass", because of its ability to determine the
direction of the sun on overcast days.
Wikipedia Information about Iolite
Moonstone is
typically a potassium
aluminium
silicate, with the chemical formula KAlSi3O8.
The
most common moonstone is of the mineral
adularia.
The
plagioclase
feldspar
oligoclase
also produces moonstone specimens. Its name is
derived from a visual effect, or sheen, caused
by light reflecting internally in the moonstone
from layer inclusion of different feldspars.
Moonstone is feldspar with a pearly and
opalescent lustre. An alternate name is
hecatolite.
Wikipedia Information
about Moonstone
Onyx is
a
cryptocrystalline
form of
quartz.
The colors of its bands range from white to
almost every color (save some shades, such as
purple or blue). Commonly, specimens of onyx
available contain bands of colors of white, tan,
and brown. Sardonyx is a variant in which
the colored bands are
sard
(shades of red) rather than black. Pure black
onyx is common, and perhaps the most famous
variety, but not as common as onyx with banded
colors.
Wikipedia Information
about Onyx
Opal is a
mineraloid gel
which is deposited at a relatively low
temperature and may occur in the fissures of
almost any kind of
rock,
being most commonly found with
limonite,
sandstone,
rhyolite,
marl
and
basalt.
The word opal comes from the Latin opalus, by Greek
opallios, and is
from the same root as Sanskrit upálá[s]
for "stone", originally a millstone with
upárá[s] for slab.
The
water content is usually between three and ten
percent, but can be as high as twenty percent.
Opal ranges from clear through white, gray, red,
orange, yellow, green, blue, magenta, rose,
pink, slate, olive, brown, and black. Of these
hues, the reds against black are the most rare,
whereas white and greens are the most common.
These color variations are a function of growth
size into the
red
and
infrared
wavelengths. Opal is Australia's national
gemstone.
Wikipedia Information
about Opals
Peridot
is a gem-quality
forsteritic
olivine.
The chemical composition of peridot is (Mg, Fe)2SiO4,
with Mg in greater quantities than Fe.
The origin of the
name "peridot" is uncertain. The
Oxford English Dictionary
suggests an alteration of Anglo-Norman pedoretés
(classical Latin paederot-), a kind of opal, rather than
the Arabic word faridat, meaning "gem".
Olivine
in general is a very abundant mineral, but gem quality peridot
is rather rare.
Peridot is one of the
few gemstones that occur in only one color: basically an olive
green. The intensity and tint of the green however depends on
how much
iron is
contained in the crystal structure, so the color of individual
peridot gems can vary from yellow-green through olive green to
brownish green. The most valuable is considered a dark-olive
green color.
Wikipedia Information about Peridot
Ruby is a pink to
blood-red
gemstone, a variety of the
mineral
corundum (aluminium oxide). The red
color is caused mainly by the presence of the element
chromium. Its name comes from
ruber,
Latin for red. Other varieties of gem-quality corundum are
called
sapphires. The ruby is considered one
of the four
precious stones, together with the
sapphire, the emerald, and the diamond.
Rubies have a hardness of
9.0 on the
Mohs
scale of mineral hardness.
Among the natural gems only
moissanite and diamond are harder.
Rubies are the July
Birthstone.
Wikipedia info about Rubies
Sapphire
(Greek: sappheiros)
is a
gemstone variety of the mineral
corundum, an aluminium oxide (α-Al2O3),
when it is a color other than red, in which case the gem would
instead be a
ruby. Trace amounts of other elements
such as
iron,
titanium, or
chromium can give corundum blue,
yellow, pink, purple, orange, or greenish color.
Wikipedia Information about Sapphire
Tourmaline
is a
crystal
silicate mineral compounded with
elements such as
aluminium,
iron,
magnesium,
sodium,
lithium, or
potassium. Tourmaline is classed as a
semi-precious stone and the gem comes
in a wide variety of colors. The name comes from the Sinhalese
word "turamali" or "toramalli", which applied to different
gemstones found in Sri Lanka.
Wikipedia Information about Tourmaline
For more information on
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