The previous article talks about the popular woman’s gemstone known as a “Moonstone”. Or the feldspar Adularia. Here on we will examine the connection of finding Adularia and gold together and why.
I was classifying these odd bluish host rock common throughout the mining claim. It classified out “Adularia”?
One research document explains how adularia naturally forms in nature.
Genesis of hydrothermal K-feldspar (adularia) in an active geothermal environment at Wairakei, New Zealand by A. Steiner (Mineralogical Magazine, Dec, 1970, Vol.37, No. 292)
Let’s paraphrase this technical article.
First, there is a major earthquake cracking surface rock; so ground water can percolate down these cracks in fissures deep in the earth. Once the geothermal boiling waters reach 265 degrees C (or roughly 509 F)., like blueberry Jell-O, the adularia melts or gels and moves up the columns of steam & heated water into cracks in bedrock.
According to A. Steiner, “Intense deposition of quartz is usually associated with the formation of hydrothermal K-feldspar (Potassium)” and his study suggests, “After crystallization, the structural state of adularia changes little, if at all, during geologic time.”
In studying hydrothermal rock alteration of drill core recovered for geothermal steam energy assets, he noticed both the bluish feldspars and white milky quartz melt in the super-heated geothermal waters; but like oil and water they never mix and they both are separate coatings for bedrock above the heating source.
Continuing our scientific investigation of Moonstone and gold factors:
Adularia Associated with Epithermal Gold Veins in the Tapajos Mineral Province…Northern Brazil by Ana M. Dreher et al (Geoscience of Brazil 28(3) pages 397 to 404, Sept.!998)
“One of the most common and at the same time, most important references to adularia is found in connection with epithermal precious and base-metal deposits, where the mineral (Adularia) occurs as a typical and distinctive gangue (overburden) phase of the so-called Adularia (hard)-Sericite (weathered soft) Deposit type… In the other category of epithermal deposit known as the acid-sulfides type, Adularia is systematically absent.”
People have a spectrum for baby to elderly and rocks have a spectrum from new or fresh to altered or decomposing soft.
“Sericite is a fine grained mica, similar to muscovite, illite, or paragonite. Sericite is a common alteration mineral of orthoclase or plagioclase feldspars in areas that have been subjected to hydrothermal alteration typically associated with copper, tin, or other hydrothermal ore deposits.
Note: Orthoclase (end member formula KAlSi3O8) is an important tectosilicates mineral which forms igneous rock. The name is from the Greek for "straight fracture," because its two cleavage planes are at right angles to each other. Alternate names are alkali feldspar, potassium feldspar and K-feldspar. The gem known as moonstone (see below) is largely composed of orthoclase.
The name comes from Latin sericus, meaning "silken" in reference to the location from which silk was first utilized, which in turn refers to the silky sheen of rocks with abundant sericite.”
Historically, most gold mines are associated with a rotten egg smelling-sulfuric acid, rusty brown iron, sulfurous sulfide minerals like pyrites, chalcopyrite, and arsenopyrites; but apparently adularia- decomposed sercite deposit offer new and very promising gold recovery prospects.
The second photo shows what the future clean gold mine deposit will look like and much less toxic!
In the book, GEOLOGY OF THE INDUSTRIAL ROCKS AND MINERALS by Robert L. Bates (Dover Publications, Inc. New York, 1969, pages 242 to 243), Bates shows how even feldspars associated by gold mining now has value in our modern economy.
“The feldspar of commerce falls within the microcline…orthoclase range. The mineral has two chief properties of value, and two major uses, dependent on these properties.
When ground to powder and used as a constituent of ceramic mixes, feldspar acts as a flux, that is, it forms glass with a ceramic body at relatively low temperatures The mineral owes this property to its content of alkalizes – potash and soda. Thus, it is a basic raw material in the manufacture of china, high-grade tile, and porcelain, as well as in white ware glaze and sheet-iron enamel.
The second property that makes feldspar of value is its alumina content, which is utilized in the manufacture of glass. Substitution of alumina for part of the silica in glass increases the resistance of the glass to impact, bending, and thermal shock.
Until about 1925, feldspar had almost no completion for the uses outline above. Since then, however, several other materials have entered the ceramic and glassmaking fields.”
Thus, modern science has discovered a new type of clean gold mining deposit.
Historic gold mining has been given a bad rap to mining; as it has used toxic and lethal cyanide and mercury to process gold and the rotten egg smell from sulfur or sulphites have leached sulfuric acid into the ground water supplies of local small mining communities.
Adularia Deposits have no sulfur /nor a need of toxic chemicals for leaching gold. Just crush and use a gold pan for concentrating this precious popular world metal.
“…Adularia occurs typically in vein lets and cavities associated with the major mineralized quartz veins”, and this “refers to the importance of this type of mineralization for the mining industry, as epithermal deposits are considered highly favorable exploration targets due to their potential for generating bulk tonnage gold deposits.”
Not all of us have a gold mining claim; but we all can still buy Moonstone relatively cheap!
“Moonstone is a very personal stone. It is a reflection of the person who owns it. It does not add or detract, only shows how it is.
This is why the moonstone is said to perceive that which "is". Moonstone is an excellent stone to use in meditation to understand oneself. Placing it in the moonlight of a moon reaching its fullness, not a full or waning moon, can revitalize it. This is a particularly good gemstone for women. It is a good stone for young women or teenagers.”
If readers ask, I’ll send you a raw moonstone!
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