Spessartine and Muscovite

ID	140
Mineral	Spessartine Muscovite
Location	Wushan Spessartine Mine - Tongbei - Zhangzhou - China
Fluorescence	LW-UV: close SW-UV: close
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Mindat data

ID	3725
Long ID	1:1:3725:5
Formula	`Mn²⁺₃Al₂(SiO₄)₃`
IMA Status	0 1
Discovery Year	1832
Diapheny	Transparent,Translucent
Cleavage	Distinct
Tenacity	brittle
Colour	Red, reddish orange, yellowish brown, reddish brown, or brown
Hardness (min)	6.5
Hardness (max)	7.5
Luminescence	Non-fluorescent
Lustre	Vitreous - Resinous
About the name	Re-named in 1832 by François Sulpice Beudant after its type locality in the Spessart Mountains, Germany. Previously distinguished as a "manganesian" garnet by Henry Seybert in 1823 using mineral from Haddam, Connecticut, USA. Originally, this mineral, from Spessart Mountains, was called "granatförmiges Braunsteinerz" in 1797 by Martin Klaproth.
Streak	White
Crystal System	Isometric
Fracture type	Sub-Conchoidal
Morphology	euhedral crystals, dodecahedra or trapezohedra, or in combination with other cubic forms, to 10 cm.
shortcode_ima	Sps
Group	Garnet Group

ID	2815
Long ID	1:1:2815:4
Formula	`KAl₂(Si₃Al)O₁₀(OH)₂`
IMA Status	0 1
Other Occurrences	Muscovite is common in many different rock types as a primary mineral.
Diapheny	Transparent,Translucent
Cleavage	Perfect on {001}.
Tenacity	elastic
Colour	White to colorless, silvery-white, and tinged various colors by impurities.
Hardness (min)	2.5
Hardness (max)	2.5
About the name	The earliest names attributable to muscovite include Muscovy Glass, Cat Silver, and Lapis Specularis (stone mirror); these names appearing in texts in the seventeenth century and before. The stand-alone name 'Muscovite' was used as early as 1794 by Johann Gottfried Schmeisser in his System of Mineralogy and is derived from the term "Muscovy glass," which was in common use by that time. Muscovy Province in Russia yielded sheet mica for a variety of uses. Muscovite and sometimes similar species were earlier called mica (Phillips and Kersey, 1706), glimmer (Phillips and Kersey, 1706), and isinglass (1747 according to OED) but all of these terms are still in use to some degree. It should be noted that mica, glimmer, and isinglass were also used for a variety of materials before these given dates and in those earlier times did not always indicate what would be a mineral, much less muscovite proper. Isinglass, for example, was originally used for a gelatinous bladder found in sturgeon.
Streak	White
Crystal System	Monoclinic
Cleavage Type	Perfect
Fracture type	Micaceous
Morphology	Crystals uncommon, tabular {001} with rhombic to hexagonal outlines, often bound by {221}, {_111} and {010} (hkl refer to -2M^1 polytype). Less common as prismatic, parallel to [001], with a crude hexagonal cross section. Most typically found as "books" and as flaky grains in various rocks. Sometimes in plumose or fibrous aggregates.
Twinning	Mica law twins common [310] forming six pointed stars, less common with the composition plane perpendicular to {001} (hkl refer to -2M^1 polytype).
shortcode_ima	Ms
Group	Dioctahedral mica

Price: € 10

Dimensions: Not registered

Weight: 8 g

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Notes:

Symbol	Element
Al	Aluminium
H	Hydrogen
K	Potassium
Mn	Manganese
O	Oxygen
Si	Silicium

Spessartine and Muscovite

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