may be Meteoric Silica Glass as a result of the impact
of a meteor on Earth. Tektites are usually found in
association with meteor impact craters or suspected
ancient craters. Their origin is not fully understood.
The leading theory, the "Meteorite Impact
Theory", is that when a meteorite hits the Earth,
the heat and pressure of the impact are so great that
it causes rock and sand to be fused into glass
or Tektites. Tektites, like all natural glasses, contain
gas bubbles and "swirl" like inclusions.
The best known Tektites are found near the
Moldau in the Czech Republic (originally Moravia).
These are known as Moldavite
and are a beautiful olive green.
interesting type of Tektite is Libyan Desert Glass.
It is a beautiful straw or champagne yellow. Libyan
Desert Glass is from the White Desert in Egypt (not
actually Libya). Until recently, these were somewhat
controversial. They were suspected to be Tektites similar
to Moldavite, but were not associated with any meteor
crator or impact zone. Researchers at the Center for
Remote Sensing at Boston University have recently discovered
a very large impact crater in Egypt 31km in diameter
which seems to coincide with the formation of Libyan
Desert Glass. This crater has been named the Kebira
Crater. The association of Libyan Desert Glass with
this newly discovered crater is tentative and further
research still needs to be done.
Tektites are found
around the world and are usually named after their location
of origin. One such Tektite is Indochinites which is
named after the region of occurrence; the former French
colonies of Indochina (Vietnam, Laos, Cambodia) plus
Thailand and southern China. These Tektites are
usually dark brown to black natural glass.
green Silica Glass suposedly found near Mt. Kilamanjaro
in Tanzania is a mysterious and controversial material
that has been called many
names including Green Obsidian, African Moldavite, Tanzanian
Green Volcanic Glass and even just glass. One source
says the Tanzanian natives call it Obsidianite. It is
reported to be found in alluvial deposits and in a river
bed at the base of Mt. Kilamanjaro. Some say it is a
natural volcanic glass, some argue that it is man-made
glass, others claim it is of meteoric origin similar
Calling it "African Moldvite" is incorrect
however, since Moldavite
only comes from the Moldau River reqion of the Czech
Republic. This deep green material, if not man-made, is
most likely to be Obsidian or volcanic glass. What ever the
source of this material or however
it was formed, it is a stunning gem of the finest Tsavorite