• Tephroite: Mineral information, data and localities.

    www.mindat.org/min-3913.html Olivine Group. Fayalite-Tephroite Series, and the Forsterite-Tephroite Series. The Mn2+ analogue of Fayalite, Forsterite, and Calcio-Olivine.
  • Tephroite - Wikipedia

    en.wikipedia.org/wiki/Tephroite Tephroite is the manganese endmember of the olivine group of nesosilicate minerals with the formula Mn 2 Si O 4.A solid solution series exists between tephroite and its analogues, the group endmembers fayalite and forsterite.Divalent iron or magnesium may readily replace manganese in the olivine crystal structure.
  • Tephroite | Definition of Tephroite by Merriam-Webster

    www.merriam-webster.com/dictionary/tephroite Tephroite definition is - a mineral Mn2SiO4 that consists of Manganese silicate and is isomorphous with olivine.
  • Tephroite Mineral Data

    webmineral.com/data/Tephroite.shtml General Tephroite Information : Chemical Formula: Mn2SiO4 : Composition: Molecular Weight = 201.96 gm Manganese 54.41 % Mn 70.25 % MnO: Silicon 13.91 % Si 29.75 % SiO 2: Oxygen 31.69 % O: 100.00 % 100.00 % = TOTAL OXIDE
  • Tephroite | mineral | Britannica

    www.britannica.com/science/tephroite Tephroite, olivine mineral found only in iron-manganese ore deposits and skarns and in metamorphosed manganese-rich sediments, such as those of Cornwall, Eng., and Franklin, N.J., in the United States. Tephroite (manganese silicate; Mn2SiO4) forms a solid solution series with the olivine fayalite
  • Tephroite | Article about tephroite by The Free Dictionary

    encyclopedia2.thefreedictionary.com/tephroite The Val Graveglia manganese mines have produced some rare and uncommon species (bementite, ganophyllite, sarkinite, sussexite, tephroite etc.) reported from just a few other famous localities, such as Langban, Sweden, and Franklin and Sterling Hill, New Jersey (Holstam and Langhof, 1999; Frondel and Baum, 1974).
  • Tephrite - Wikipedia

    en.wikipedia.org/wiki/Tephrite Tephrite is an igneous, volcanic rock, with aphanitic to porphyritic texture. Mineral content is usually abundant feldspathoids (leucite or nepheline), plagioclase, and lesser alkali feldspar. Pyroxenes (clinopyroxenes) are common accessory minerals. Quartz and olivine are absent. Occurrences include leucite nepheline tephrite from Hamberg bei Neckarelz near Heidelberg, Germany, tephritic ...
  • Tephroite: The mineral tephroite information and pictures

    www.minerals.net/mineral/tephroite.aspx Tephroite is uncommon member of the Olivine group. It is the manganese counterpart of Forsterite, and forms a series with Forsterite. Tephroite gets it name from the Greek word "tephros", meaning ash-colored, referring to its ash-gray color habit.
  • Tephroite Value, Price, and Jewelry Information ...

    www.gemsociety.org/article/tephroite-jewelry-and-gemstone-information Tephroite is generally reddish brown and barely translucent. However, it takes a good polish and is massive enough to make good cabochons. Only the New Jersey and Australian localities seem to have provided such material, however. Faceted gems are unknown.
  • Tephroite Mn2+ SiO 2 4 - Handbook of Mineralogy

    handbookofmineralogy.org/pdfs/tephroite.pdf Tephroite Mn2+ 2 SiO4 °c 2001 Mineral Data Publishing, version 1.2 Crystal Data: Orthorhombic. Point Group: 2=m 2=m 2=m: Crystals typically short, prismatic, to 4 cm, or anhedral, equidimensional.