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Roger Weller, geology instructor
by Kiah Taylor
Looking around for minerals? Have you ever heard of kKyanite? It's all
around you in sinks, and sparkplugs, its used to cut tools, or even in jewelry,
but do you know what it really is or what it even looks like? Well lets see if
this paper can fix that.
Kyanite like all the other minerals is a very unique one. It is mostly found in metamorphic rocks. It is found in schists (metamorphic rock with well-developed foliation) and gneisses (foliated metamorphic rock that has a banded appearance and is made up of granular mineral grains). It is formed from high pressure alterations in clay minerals during the metamorphism stage of sedimentary rocks. While knowing that kyanite is usually from schists and gneisses it is also associated with garnets (a group of very common rock-forming minerals), staurolite (a mineral that is commonly found in metamorphic rocks), and corundum (an abrasive made famous by rubies and sapphires), that are all other metamorphic minerals.
Kyanite is considered a “cousin” to sillimate and alusite, for the
fact they are all polymorphs. They are called that because they are three
distinct minerals, but all of them have the same chemical formula (Al2Si05-aluminum
silicate). With them all being similar they can be used for the same things. But
they have there differences. Focusing on kyanite, it has a glassy luster,
and one thing that’s really unique about it is the two different hardnesses.
Depending on if you go across or down the crystals surface. If you go across
the crystal it is a seven on the hardness scale, but going down the crystal it
is only a five. Kyanite is the only mineral that has two hardness
regardless of where it is measured at.
The primary color for kyanite is blue. The mineral has several different shades ranging from light blue to dark blue, white, gray, yellow, pink, orange and black. Green kyanite is a rare color you would found, however some Kyanite can be zoned. The term zoned means having two different colors in one stone.
chart shows birefringence interference color range (at 30µm thickness) and does
not take into account mineral coloration.
Did you know kyanite has many industrial uses? Some qualities to the
stone is the hardness of the surface, it is heat resistant, and excellent for
grinding and cutting wheels. Many steel production companies will have
great use for kyanite. Along with other materials, kyanite can be used as
a refractor materials because it is resistant to very high temperatures.
Some examples of refractories produced are nonferrous (non-iron bearing) metals
and ceramics like porcelain.
is used as a heat resistant binding medium in cutting tools and grinding wheels.
© iStockphoto / Ron Sumners http://geology.com/minerals/kyanite.shtml)
porcelain insulator on this spark plug was made with kyanite.
© iStockphoto / Juergen Barry http://geology.com/minerals/kyanite.shtml)
The over all quality to kyanite is a great resource in the industrial business. When it is heated it can expand significantly (unlike most minerals) and depending on the size of the particle temperature and heating conditions, kyanite could double its original volume. You can also add into raw materials which will shrink during heating, to keep the volume in the finished product.
Another use of kyanite is in gemstones. With it ranging from transparent to
translucent and going over the color spectrum, it can be highly prized by
gemstone cutters. Many people cut and facet gemstones to turn them into beads or
pendants. While it is not the most common gemstone (kyanite) is used in jewelry
out there, but some people consider it to be exotic for that fact.
Another interesting fact and use for kyanite is for metaphysical purposes. Did you know it can help ease the mind and emotions? Kyanite can be used for aligning all your chakras automatically and immediately. Other uses are for facilitating deep and meaningful meditations, and helping with the recall of dreams. The different color stones contribute to different meanings/outcomes. For example, the black Kyanite assists in grounding, where the orange kyanite is said to help activate and open the second chakra. A benefit to the stone/mineral is it never needs cleaning and doesn’t absorb negative energy.
Angelic Therapeutic Metaphysical Pendant by Divine Crystal Souls
Looking more into the history of kyanite, you will find that it was
named in 1789 by Abraham Gottlieb Werner. From the Greek word “Kyanos” meaning
blue, the common color of the species. “Cyanite” (the French spelling) was
commonly used through must of the 19th and early 20th
centuries by mineralogists. The term Kyanites “grandfathered” prior to 1959 and
other minerals very similar to kyanite are disthere, and rhaeticite.
Over all kyanite is a unique mineral, with different uses/purposes and different colors. I hope you now know more about kyanite than you did before and can share with others.