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Almandine
Most remaining red garnets (usually a deep,
violet-red) come under the name of almandine, even when their
composition is midway between that of pyrope and almandine
and similar, in many cases, too that of rhodolite. The reason
for this is the similarity in their color and absorption spectrum
characteristics. The name almandine come from carbunculus
alabandicus, after the city of Alabanda in Asia Minor, where
gems were traded at the time of Pliny the Elder (carbunculus,
as already explained, means “small coal” and has
been used to refer to red stones in general)
Appearance The color is red, but often a
deep, violet-red. It has brilliant luster, but its transparency
is frequently. marred, even in very clear stones, by excessive
depth of color. The cabochon cut is widely used, often being
given a strongly convex shape and sometimes a concave base,
it an effort to lighten the color by reducing the thickness
Rose cuts have also been used, particularly in the past Nowadays,
when the material is quite transparent, faceted cuts are used
as well, and sometimes square or rectangular step cuts. Gems
of several carats are not uncommon Faceted or even barely
rounded pieces of almandine pierced as necklace beads, were
very common in the recent past, but are now considered old-fashioned.
Distinctive features The deep, almost violet-red
is fairly, typical, and has given rise to the expression garnet
red It is not enlivened, as are dark rubies, even by strong
light and its single refraction and lack of visible pleochroism
should normally distinguish it from similarly colored rubeilite.
If fairly transparent faceted stones are viewed from above,
some of the facets often look black on the inside (this is
known as the garnet effect ). Almandine has a luster comparable
to that of corundum. It is not easily distinguished from spinel,
except by examining the physica properties, which can vary
quite considerably, according to the composition: the density
is between 3.95 and 4.2C g/cm3, or thereabouts; the refractive
index varies frorr 1.76 to 1.83 (the density increases parallel
to the index). It has a hardness of about 6-7.5.
Occurrence Almandine is obtained in large
quantiv from Sri Lanka and India, where it is also cut; other
sour _ are Burma, Brazil, the United States, Madagascar, Tan:
nia, and Australia.
Value This depends on brightness of color
and freea from cracks and inclusions, but is always quite
low mandine was extremely popular in the nineteenth cent~.
but the name "garnet is now automatically associa, with
cheap stones.
Simulants and synthetics Almandine has been
imita* by glass, which can look very similar. It has apparer
been produced synthetically, but not on a commer: basis.
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