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Sphalerite, also known as blende or zinc blende, is the major ore of zinc. When pure (with little or no iron) it forms clear to white crystals (known as Cleiophane ). Yellow to orange sphalerite is often called "golden sphalerite." Red shades of sphalerite are known as Ruby Blende or Ruby Jack. As iron content increases, sphalerite forms dark ...General Sphalerite Information : Chemical Formula: (Zn,Fe)S : Composition: Molecular Weight = 96.98 gm Zinc 64.06 % Zn Iron ... Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern. Habit: Colloform - Forming from a gel or colloidal mass. Habit:Sphalerite makes an excellent collector’s stone, but it is too soft for jewelry. It is difficult to cut and polish due to perfect cleavage in six directions. Gemstone-quality material, when faceted, is remarkable due to its incredibly high dispersion. Sphalerite (sometimes spelled sphaelerite) is a sulfide mineral with the chemical formula (Zn,Fe)S. It is the most important ore of zinc.Sphalerite is found in a variety of deposit types, but it is primarily in sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfides), calcite ...1. Sphalerite - color resinous yellow to dark brown; cleavage perfect in six directions; soft. 2. Amphibole - color dark green to black; cleavage in two directions. 3. Biotite - color brown to black; cleavage perfect in one direction (cleaves into flexible, elastic sheets). 4. Feldspar - color variable, occasionally dark grey; cleavage excellent inSphalerite has perfect cleavages in six directions, some of which are easy to produce, others hard - hence you won't always see all six cleavage surfaces in any given sample of the material. Microcline feldspar, South Dakota, 4cm long. Perfect cleavage is the right face. Good cleavage is the top faceFigure \(\PageIndex{1}\): Round Brilliant Sphalerite Photo courtesy of Rick Martin, Art Cut GemsOrienting along the 3-fold axis leaves us with 6 cleavage planes on the girdle. Not good, but if you orient the girdle facets at skew to the cleavages, its ...Acanthite is a form of silver sulfide with the chemical formula Ag 2 S. It crystallizes in the monoclinic system and is the stable form of silver sulfide below 173 °C (343 °F). Argentite is the stable form above that temperature. As argentite cools below that temperature its cubic form is distorted to the monoclinic form of acanthite.The sphalerite crystallizes in cubic system with perfect cleavage, and simple contact twinning. Sphalerite depicts uneven to conchoidal fracture, adamantine, resinous to greasy luster, and brownish white to pale yellow streak. The specific gravity is between 3.9 and 4.2, and hardness between 3.5 and 4.0.3.26 Dark metallic sphalerite with orange resinous sphalerite on top 3.27 Amber with an included insect. The photo on the right above shows ... The play of colors is due to a layered atomic arrangement, so pearly minerals generally have excellent planar cleavage. The two photos below show pearly muscovite and talc. These minerals are somewhat ...Figure 4.6.5 4.6. 5: Some minerals have different streaks than their visual color. Streak examines the color of a powdered mineral and can be seen when a mineral sample is scratched or scraped on an unglazed porcelain streak plate. A paper page in a field notebook may also be used for the streak of some minerals.Cleavage: Yes 6 perfect cleavages: Streak: Pale Yellow: Color: Yellow Brown to Black: Miscellaneous: Powdered streak smells like rotten eggSphalerite is usually faceted in order to maximize its brilliance and can be seen in a variety of shapes, such as octagons, trillions, squares, rounds and fancy shapes, such as ovals, pears and cushions. Sphalerite is a challenge to gem cutters because of its brittle tenacity, softness and perfect cleavage in six directions.Comments: Lustrous sharp crystals of pyrrhotite to 3.5 cm in size with minor sphalerite and chalcopyrite. Location: Nikolaevskiy mine, ... Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern. Habit: Massive - Granular - Common texture observed in granite and other igneous rock. Habit:Sphalerite. Type: Mineral: Luster: Nonmetallic Resinous: Hardness: 3.5 - 4 > Fingernail but < Glass: Cleavage: Yes 6 perfect cleavages: Streak: Pale Yellow: Color: Yellow Brown to Black: Miscellaneous: Powdered streak smells like rotten egg: East Carolina University Department of Geological SciencesDodecahedral cleavage: some high symmetry minerals may have six cleavage planes that intersect in space separating small dodecahedrons (e.g. sphalerite). Pinacoidal …

Although sphalerite (SFAL-er-ite) has a hardness of only 3 1/2 to 4 and possesses six directions of perfect dodecahedral cleavage, transparent stones are highly prized by collectors because of the mineral's tremendous dispersion (0.156) and R.I. (about 2.37). The resultant brilliancy and fire displayed by green, greenish-brown, yellow-brown or ...Cleavage/Fracture: Cleavage is dodecahedral in 6 directions of perfect cleavage, and fracture is conchoidal meaning it resembles the shape of a scallop shell. (3, 1) Crystal Form: Most commonly, sphalerite is found shaped as tetrahedral crystals, with a pyramid-type shape. The crystal faces are usually somewhat rounded or curved. SPHALERITE - ZnS Sphalerite (old names: “blende ”, “zinc blende”) is a common sulfide and the main ore of Zn. May constitute a Cd ore. Sphalerite is usually massive. Crystals are rare, tetrahedral and dodecahedral, typically very complex and distorted (conical and curved faces); can look like octahedrons, reach 30 cm. Twins are common,Sphalerite ( ( Zn, Fe) S) is a mineral that is the chief ore of zinc. It consists largely of zinc sulfide in crystalline form but almost always contains variable iron. When iron content is high it is an opaque black variety, marmatite. It is usually found in association with galena, pyrite, and other sulfides along with calcite, dolomite, and ...

Black Jack. Blende. Zinc Blende. VARIETIES. Cleiophane. - Transparent, lightly colored variety of Sphalerite. Marmatite. - Opaque, metallic luster ed, ironrich variety of …Figure \(\PageIndex{1}\): Round Brilliant Sphalerite Photo courtesy of Rick Martin, Art Cut GemsSphalerite makes an excellent collector’s stone, but it is too soft for jewelry. It is difficult to cut and polish due to perfect cleavage in six directions. Gemstone-quality material, when faceted, is remarkable due to its incredibly high dispersion. …

Reader Q&A - also see RECOMMENDED ARTICLES & FAQs. ... sphalerite (as measured via sodium light, 589.3 nm) is 2.37. Sph. Possible cause: Sphalerite has been mined from the Hutson Mine in Livingston County, and the Lexi.