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What are the Uses for Quartz?
Quartz is one of the most useful natural materials. Its usefulness can be linked to its physical and chemical properties. It has a hardness of seven on the Mohs Scale which makes it very durable. It is chemically inert in contact with most substances. It has electrical properties and heat resistance that make it valuable in electronic…
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Where is Quartz Found?
Quartz is the most abundant and widely distributed mineral found at Earth’s surface. It is present and plentiful in all parts of the world. It forms at all temperatures. It is abundant in igneous, metamorphic, and sedimentary rocks. It is highly resistant to both mechanical and chemical weathering. This durability makes it the dominant mineral of mountaintops and the primary…
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What is Quartz?
Quartz is a mineral composed of silicon and oxygen, with a chemical composition of SiO2. It is the most abundant mineral in Earth’s crust and is resistant to both chemical and physical weathering. When rocks weather away, the residual material usually contains quartz. This is why the sand at most of the world’s beaches is quartz.
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Topaz Misnomers
The name “topaz” has often been used incorrectly or inappropriately in conversation and commerce. These incorrect uses of a name are called “misnomers”. Misnomers can be used in three ways: The word topaz is used in all of the above ways and perhaps more. A list of topaz misnomers is provided below with a brief…
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Sources of Topaz
Topaz is found in many locations worldwide where rocks like pegmatite and rhyolite are formed. Here, topaz is usually a minor mineral in terms of quantity, and a secondary mineral in terms of its time of formation. Brazil has been the world’s most important source of topaz for decades. Almost all of the world’s fine-quality imperial…
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Geologic Occurrence of Topaz
Topaz has a chemical composition of Al2SiO4(F,OH)2. The fluorine in its composition is a limiting factor on its formation. Fluorine gas in concentrations high enough to form minerals only occurs in a few geologic environments. Most topaz grows as crystals within the veins and voids of igneous rocks. This topaz is found in the cavities of…
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Radioactive Blue Topaz?
The type of irradiation used to transform colorless topaz into blue topaz can cause the irradiated material to become slightly radioactive. Fortunately, the radioactivity level of the topaz begins to decline as soon as treatment is complete. It eventually declines to a level that is safe for the topaz to be handled during manufacturing and…
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Topaz Treatments
Today most topaz offered in department stores and mall jewelry stores at low to moderate prices has been treated in a laboratory. Colorless topaz can be heated, irradiated, and coated with thin layers of metallic oxides to alter its color. Natural blue topaz is extremely rare and is usually pale blue. Almost all of the…
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Use of Topaz as a Gemstone
The name “topaz,” and variants of the name in other languages, have been used for yellowish gemstones for at least two thousand years. At that time yellowish gems were called “topaz” in many parts of the world. Many of the earliest gem traders did not realize that these yellowish stones were actually different materials. Then, about two…
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What Color is Topaz?
Topaz occurs in a wide range of natural colors; however, most natural topaz is colorless. The most highly regarded colors are the reds and pinks, which receive their color from trace amounts of chromium. Chromium is also responsible for the color in violet and purple topaz. A variety known as “imperial topaz” is especially valuable…