Authentic Occurrence   -          ARTISAN CRAFTED JEWELRY & FINE ARTS
 
GEMOLOGY 101
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Welcome! I have been asked to create a learning library of sorts for educational purposes. I decided to create this page to represent a gemstone each month.
 
 
There is a vast array of resources available to expand upon the representation here. In the future,I will be adding more items such as fossils, megalodon and mineral specimens.
 
Featured specimens can be found in the library  
 
 
If you have a "thirst for knowledge" ..... Please bookmark the page and visit it often!
 
 Fossils:
Orthoceras
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Goniatites were an early form of curved cephalopd. They are part of the ammonite family. The suture pattern has a zig zag appearance that is very distinctive. Goniatites lived from the middle of the Devonian Period to the end of the Permian Period which closed out the Paleozoic Era
 
Ammonites were a type of cephalopod that appeared in the fossil record during the Devonian Era. They are related to squid and octopus. The nautilus is their closest living relative. The ammonite shell had sections, with the living animal occupying only the section of the shell closest to the head. As the soft-bodied ammonite got larger, it grew a new shell section and sealed off the old one with a layer called the septa. All ammonites became extinct 65 million years ago.
 
 
      Carcharodon Megalodon
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Carcharodon Megalodon was a giant shark that lived during the Miocene and Pliocene epochs of the Cenozoic Era, between 2 million and 16 million years ago. Little is known for sure about these giant predators because all that remains of their existence are fossilized teeth. But what teeth they are! These giant shark teeth range in size from 3 inches long to 7 inches long. They are massive things that can be bigger than a man’s hand. It sets the imagination reeling. To put this in perspective a large great white shark measures about 20 feet long and weighs a little over 2 tons. A tooth from a shark like this is about 1.5 inches long.
 
The fossilized teeth are all that remains of this monster because sharks do not have bones. Their skeleton is made up of cartilage. This is what your ears and nose are made from. Cartilage does not fossilize well.
 
The white shark is its closest living relative. This is well accepted but sets the stage for debate over the family tree
    
 
Geodes
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are geologicalrock formations which occur in sedimentary and certain volcanic rocks. Geodes are essentially rock cavities or vugs with internal crystal formations or concentric banding. The exterior of the most common geodes is generally limestone or a related rock, while the interior contains quartz crystals and/or chalcedony deposits. Other geodes are completely filled with crystal, being solid all the way through. These types of geodes are called nodules.
 
 
 
 
Alligator Teeth
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are hollow. New teeth are formed under/inside existing teeth and continue to be replaced by newer ones.This occurs every two years. The teeth in front are replaced more often than teeth to the rear of the mouth 
 
 
Amber
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is fossilized tree resin, which has been appreciated for its color and natural organic beauty since Neolithic times. Amber is used as an ingredient in perfumes, as a healing agent in folk medicine, and as jewelry. There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions. Amber occurring in coal seams is also called resinite, and the term ambrite is applied to that found specifically within New Zealand coal seams
 
 
Kyanite
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Kyanite, whose name derives from the Greek word kuanos sometimes referred to as "kyanos", meaning deep blue, is a typically blue silicatemineral, commonly found in aluminium-rich metamorphic pegmatites and/or sedimentary rock.
 
Kyanite is used primarily in refractory and ceramic products, including porcelain plumbing fixtures and dishware. It is also used in electronics, electrical insulators and abrasives. Kyanite has been used as a gemstone, though this use is limited by its anisotropism and perfect cleavage. Kyanite is one of the index minerals that are used to estimate the temperature, depth, and pressure at which a rock undergoes metamorphism.
 
Kyanite's elongated, columnar crystals are usually a good first indication of the mineral, as well as its color (when the specimen is blue). Associated minerals are useful as well, especially the presence of the polymorphs or staurolite, which occur frequently with kyanite. However, the most useful characteristic in identifying kyanite is its anisotropism. If one suspects a specimen to be kyanite, verifying that it has two distinctly different hardnesses on perpendicular axes is a key to identification.
 
 
 
Volcanic Rocks
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are named according to both their chemical composition and texture. Basalt is a very common volcanic rock with low silica content. Rhyolite is a volcanic rock with high silica content. Rhyolite has silica content similar to that of granite while basalt is compositionally equal to gabbro. Intermediate volcanic rocks include andesite, dacite, trachyte, and latite.
 
 
 
 
 
 
 
September - Sapphire
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Pronounced
( saf ir' )
 
September's birthstone has come a long way since the days when any and every blue stone was called a sapphire. Though its fame is shared with its "Big Three" counterparts ruby and emerald, sapphire has enjoyed a long run as one of the world's most beloved gemstones, earning itself a place of honor in crown jewels, royal accessories, museums, and even in modern royal engagement rings. Lest sapphire get too haughty, it has common uses as well. The rough polishing material on emery boards is made up of lower-quality corundum grains, strengthened with hematite, magnetite, and quartz.
 
Name Origin and Meaning
The word "sapphire" comes from the Greek word sappheiros or sapphirus, which is derived from the Hebrew sappir. However, according to Pliny's Natural History, while the stone referred to as sapphirus was blue, it was not transparent and, as he noted in more than one instance, was speckled with gold, leading scholars to believe that it was lapis lazuli instead of sapphire. In other ancient texts, the word cyanus appears to refer to the stone we now know as sapphire, from the Greek root word cyan, meaning "blue."
 
Phenomenon
When cut en cabochon, some sapphires display a four- or six-rayed star known as asterism. Blue star sapphires are one of the most valuable star stones, second only to their red star ruby cousins. Black star sapphires are also quite rare and valuable, though black stars are often more fragile than other star sapphires and, interestingly, are actually dark brown, not black.Color-change sapphire also exists, changing
 
Discovery and History
Sapphire has a long and storied history that has no clear beginning. Highlights include mentions of it in the Bible as well as in ancient scholarly texts like Pliny's Natural History. Sapphire has been prized for thousands of years not only for its beauty but also for its supposed powers, usually related to eyes or vision, thanks to sapphire's calming blue hues. To wit: An oval blue sapphire set in a gold ring was among the possessions of France's King Charles V during the 14th century, apparently used to touch and soothe the eyes, and clergymen in the Middle Ages wore rings set with blue sapphires prized for their "heavenly" blue color.
 
Sapphire began writing itself a more factual history when 18th-century gemologists began using the term "corundum" to describe blue stones of a particular hardness. While still not exact, it was a step in the right direction and a big improvement over the days when every blue stone was called sapphire. Since then, sapphire's history has been closely tied to the Kashmir region of Pakistan and India, the source of the world's finest, most prized sapphires, both then and now.
 
Care:
Ranking a hard 9 on Mohs' scale, sapphire is safely cleaned with warm soapy water and a soft brush. As long as it's not oiled or glass-filled, sapphires and sapphire jewelry should be safe in ultrasonic and steam cleaners. Be careful to avoid particularly harsh detergents and aggressive scrubbing with oiled sapphires.
 
Value:
According to GIA's color grading factors for colored stones, the most valued sapphires are velvety violetish blue to blue in medium or medium-dark tones with strong to vivid saturation. Because almost all sapphires are heated to improve or alter their color and/or their clarity, natural unheated sapphires are quite rare and much more valuable than their heated counterparts. Natural blue and yellow sapphires in particular are sought by collectors and regularly fetch impressive prices. For other sapphires, the intensity and saturation of color, followed by clarity and size, are the factors that determine the stone's value. Orangy-pink padparadscha sapphires, as well as the famed silky blue Kashmir, Burmese, and Ceylon (Sri Lankan) sapphires, are typically among the most valued.
 
Color
While the color blue immediately comes to mind when one thinks of sapphire, sapphire actually comes in all colors of the rainbow--except red, because red corundum is called ruby.
 
 
 
Crystal
Formations
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The process of forming a crystalline structure from a fluid or from materials dissolved in the fluid is often referred to as the crystallization process. In the old example referenced by the root meaning of the word crystal, water being cooled undergoes a phase change from liquid to solid beginning with small ice crystals that grow until they fuse, forming a polycrystalline structure. The physical properties of the ice depend on the size and arrangement of the individual crystals, or grains, and the same may be said of metals solidifying from a molten state.
Which crystal structure the fluid will form depends on the chemistry of the fluid, the conditions under which it is being solidified, and also on the ambient pressure. While the cooling process usually results in the generation of a crystalline material, under certain conditions, the fluid may be frozen in a noncrystalline state. In most cases, this involves cooling the fluid so rapidly that atoms cannot travel to their lattice sites before they lose mobility. A noncrystalline material, which has no long-range order, is called an amorphous, vitreous, or glassy material. It is also often referred to as an amorphous solid, although there are distinct differences between crystalline solids and amorphous solids: most notably, the process of forming a glass does not release the latent heat of fusion.
Crystalline structures occur in all classes of materials, with all types of chemical bonds. Almost all metal exists in a polycrystalline state; amorphous or single-crystal metals must be produced synthetically, often with great difficulty. Ionically bonded crystals can form upon solidification of salts, either from a molten fluid or upon crystallization from a solution. Covalently bonded crystals are also very common, notable examples being diamond, silica, and graphite. Polymer materials generally will form crystalline regions, but the lengths of the molecules usually prevent complete crystallization. Weak van der Waals forces can also play a role in a crystal structure; for example, this type of bonding loosely holds together the hexagonal-patterned sheets in graphite.
Most crystalline materials have a variety of crystallographic defects. The types and structures of these defects may have a profound effect on the properties of the materials
 
 
 
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