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Microcline Feldpsar Metaphysical Properties
In the earth's crust, feldspars are more abundant than all other minerals combined. The majority of the common feldspars fall into two groups, the alkali feldspars (KAlSi3O8 through NaAlSi3O8 series), and the plagioclase feldspars (NaAlSi3O8 through CaAl2Si2O8 series). Microcline (KAlSi3O8) is the low temperature pure potassium end member of the alkali feldspar specimens group.
At high temperatures, the alkali feldspars form a continuous
solid solution series, however at medium to low crystalization
temperatures the sodium feldspar (albite) and potassium feldspar specimens
(microcline or orthoclase) separate forming lattice type exsolution
intergrowths, usually as thin layers of albite roughly parallel to
{100} in a host crystal of microcline or orthoclase. This is known
as perthitic texture.
Adularia is an unusual gem variety of the
potassium feldspar orthoclase. It exhibits an iridescence most commonly known as
moonstone (also known as adularescence),
which is due to diffused light reflection
from microscopic parallel intergrowths of albite and orthoclase.
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Microcline commonly occurs in plutonic igneous rocks such as granites and syenites that cooled slowly and at considerable depth. It is the common potasium feldspar variety in pegmatites where it can form the largest known crystals of any mineral (in a pegmatite in Karelia, U.S.S.R., a microcline mass weighing over 2000 tons showed the form of a single crystal!). Microcline and quartz (often as smoky quartz) can crystalize simultaneously in pegmatites in an interpenetrating pattern known as graphic granite. The rare variety of green microcline known as amazonite also occurs in pegmatites. Its green color is thought to be due to trace impurities of lead and OH-1. Microcline is also common in metamorphic rocks in gneisses, and in sedimentary rocks in arkoses and conglomerates.
Microcline is distinguished in thin section from orthoclase (the medium
temperature polymorph of potassium feldspar which is chemically identical
to microcline) by the presence of tartan twinning. In the field
the indicators are color, transparency, occurance and luster.
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The name microcline comes from two Greek words meaning little and inclined, referring to the cleavage angle's slight inclination from ninety degrees. Feldspar is derived from the German word feld which means field.
The green variety of microcline amazonite is used as an ornamental lapidary material.
Microcline is used mainly in the manufacture of porcelain. It is ground very fine and mixed
with kaolin and quartz. Upon heating, the feldspar fuses and acts as a
cement binding the materials together. Fused feldspar also is the main
constituent in the glaze on porcelain. Sometimes feldspar is also used to
supply alumina in the manufacture of glass.
The astrological sign of microcline is Libra.
The astrological sign of amazonite is Virgo.
Amazonite is an alternate birthstone for the month of December.
Microcline is said to stimulate clarity of thought, to
enhance understanding, and to improve one's ability to
cooperate with others. Microcline is also said to help treat eye disorders
and fevers. It also is said to control water retention and to help with
ease of childbirth.
Amazonite is said to calm one's emotions
and soothe nerves, and to enhance creativity and the ability
to express oneself. The deeper the color of the amazonite, the more
intense the effect is said to be. Amazonite is said to help aleviate muscle
spasms and to help normalize calcium levels in the body, and
to help relieve stress and exhaustion.
For more in-depth metaphysical information, see our Metaphysical Books section.
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