MUSCOVITE MICA AUSSIE SPECIMEN
Large Muscovite Mica Aussie Specimen on Feldspar. Featuring many slim sheets of Mica on a hefty Feldspar Matrix. This lovely silvery Mineral possesses special real scientific properties like electrical, thermal and electromagnetic insulation and shielding. We have measured these properties with a Trifield meter for shielding. Mica is one of the best natural radiation shields.
Mica can be flaky and comes apart in thin sheets much like flexible plastic. It is a popular and unusual mineral that appeals to people of all ages. Muscovite is just one variety of Mica, named for the Russian province of Muscovy, known for its sheet mica. Interestingly during WW2 Germany was the first to produce lab grown Mica. Using thermal control with an applied Electromagnetic Force Perpendicular to the growth plane. This is very interesting considering they used an EMF to control the growth of large flat crystals.
24cm x 15cm x 16cm, 7300g.
KAl2(AlSi3O10)(OH)2 MICA GROUP
The Micas are an important group of minerals. interesting is how resistant and durable mica crystals can be. Thin flakes of mica are generally flexible and brittle, resistant, durable in withstanding high temperatures and pressures in metamorphic conditions.
Resisting the punishment of erosional environments. Most people know about the three most common mica minerals. Muscovite, Biotite, and Lepidolite. Less common Micas Glauconite, Paragonite, Phlogopite and Zinnwaldite. The Mica Group is large with over 30 members.
A large group with 20 odd members, nine are well known. They make up the greatest percentage of minerals found in the Earth’s crust.
The feldspars are a group of minerals that have similar characteristics due to a similar structure. All feldspars have low symmetry, being only monoclinic, 2/m, to triclinic, bar 1. They are slightly hard at around 6, and have an average density at 2.55 to 2.76. They have a rather dull to rarely vitreous luster. Crystals tend to be blocky. Some feldspars may be triboluminescent. They have two directions of cleavage at nearly right angles. Feldspars also tend to crystallize in igneous enviroments, but are also present in many metamorphic rocks.