|
|
|
Petalite
A rare mineral, Petalite generally occurs in pastel yellow, ranging
to pink and colorless. It was discovered on the Swedish island of Ut Arfvedson
by the Brazilian scientist Jos Bonifácio de Andrada e Silva while he was
visiting Sweden towards the end of the 18th century. The name 'Petalite'
is derived from the Greek 'Petalon' meaning 'Leaf' and 'Lithos' meaning
'Stone' alluding to its leaf-like cleavage.
|
|
Petalite is most commonly
found in cleavable masses without crystal form. However, it sometimes
forms nice crystals occurring as tabular or columnar prisms with glassy
appearance. These fine quality crystals are rather rare and fragile. For
this reason Petalite is only occasionally cut as a gemstone. The occurrence
of Petalite has been reported in Brazil, Australia, Sweden, Finland, USA,
Zimbabwe, Namibia and Elba in Italy. The major sources for nice, transparent
and facetable stones are Brazil and Namibia.
Commonly found in Lithium-bearing pegmatite, Petalite is composed of Lithium,
Aluminium, Silicon, and Oxygen (LiAlSi4O10). It has a relative hardness
of 7 and a Specific Gravity of 2.4.
Petalite is a very unique mineral that offers some beautiful pastel colors.
It owes its limited desirability to rarity, but definitely deserves a
place in collections, especially in larger sizes.
Petalite can be cut into bright stones with a vitreous luster. As it rarely
occurs in large crystals, be prepared to see mainly small stones when
shopping for Petalite. A specimen that weighs in above 2.0 carats is considered
a rather large Petalite. Although it is more of a collection mineral,
it will be a great conversation starter wearing Petalite jewelry to a
party when no one else has it.
|