Peridot is the August birthstone. The stone is also
known as Chrysolite. It is a variety of the mineral Olivine, which is
Magnesium Iron Silicate. Peridots are found in nature only in one color
which is characteristic of the stone. The color is yellowish green or
golden green, and is caused by the presence of Iron 2.The hardness of the
stone is 6.5 to 7.0 on the Mohr's Scale, which is equivalent to a medium hardness. Peridot forms orthorhombic crystals with two refractive indices and a
fairly high birefringence,
giving rise to double images when viewing through the crystal. The facet
junctions and inclusions
are strongly doubled when viewing the stone through its table.
Peridot is an ancient gemstone known to the Egyptians
as far back as 2,000
years B.C. Most of the peridots at that time came from a volcanic island in the red sea, known as
St. John's Island. Peridots
were also known to the ancient Romans and was quite popular during the
medieval period in Europe.
After this period the stone had remained forgotten for a very long time, until interest in the
stone was rekindled again in the 1990's.This was after a large and rich
deposit of good quality
peridots was discovered in Pakistan, in a mountainous terrain about,4,000
meters above sea level. The area was covered with snow during the winter
period, and mining of the
gemstones were possible only during summer time These peridots are sold as Kashmir peridots and
are of very high quality
with fine clear crystals and a rich green color.
Peridots are also found in
Afghanistan, Myanmar (Burma), China, Australia, Africa, Brazil, and Arizona
and New Mexico in the U.S.A. Peridots are usually smaller in size falling
within the range of 5 to
15 carats, but larger peridots of around 50 carats have been found in Burma
and in Pakistan peridots
of more than 100 carats have been reported.
Peridot has been used in ancient times as a magic and healing stone and is
believed to protect one from nightmares and grant power and influence to the wearer.