moldavite (Tektite)
These
natural green meteoric, translucent gemstones are found in the
Moldavites
were formed about 15 million years ago when a meteor collided with the Earth
with devastating force. The kinetic energy transformed into
thermal energy within a fraction of a second and brought about the formation of
hot liquid magma which was then catapulted back into the atmosphere. The
dispersed mass descended again on the Earth in the form of molten drops
showering over hundreds of kilometers. Due to complex geological and tectonic
processes, the vast majority of the moldavite mass was destroyed by gradual
erosion. Only minor deposits of the original sediments have been preserved until
now. As their sculptation can be easily damaged, the stones
have to be mined manually and the gravel containing moldavite carefully sorted.
For this reason, moldavite is a very rare precious stone to
be found only in a few localities in southern
On the Mohs scale of hardness they rate anywhere from a 6.5 to 7. Diamond is a 10 and common glass about a 5. The melting point of Moldavite is 1400 degrees, whereas glass is about 1100 degrees. They contain silica and various metallic oxides, including alumina, low amounts of iron oxides and potassium oxide. They have an extremely low water content. Moldavites often contain bubbles which have a rather high vacuum, equaling the air pressure at a height of around twenty kilometers.
Stone Age man prized these stones as tools and later as talismans and jewels. In legend, Moldavite is associated with the fabled Stone of the Holy Grail, which was said to be an emerald that fell from the sky, out of the crown of an angel. Exposure to the Stone of the Grail was said to quicken one's spiritual evolution.