Revision as of 01:35, 19 September 2010 editVsmith (talk | contribs)Administrators272,935 edits +← Previous edit | Revision as of 04:03, 29 September 2010 edit undoSncervantes (talk | contribs)18 editsNo edit summaryNext edit → | ||
Line 1: | Line 1: | ||
'''Annite''' is a ] mineral in the ] family. It has a chemical formula of KFe<sub>3</sub><sup>2+</sup></sup>AlSi<sub>3</sub>O<sub>10</sub>]. | '''Annite''' is a ] mineral in the ] family. It has a chemical formula of KFe<sub>3</sub><sup>2+</sup></sup>AlSi<sub>3</sub>O<sub>10</sub>]. | ||
<ref name=Mindat></ref> Annite is the ] |
<ref name=Mindat></ref> Annite is the ] end member of the ] mica group, the iron rich analogue of ] rich ].<ref>Deer, W. A., R. A. Howie and J. Zussman, ''An Introduction to the Rock Forming Minerals,'' Longman, 1966, p. 212 ISBN 0582442109</ref> | ||
Annite was first described in 1868 for |
Annite was first described in 1868 for the first noted occurrence in ], ], ], USA and on Pikes Peak, El Paso Co, Colorado.<ref name=Mindat/> It occurs in ] and ] that are deficient in magnesium. It occurs associated with ] and ] in the ].<ref name=HBM></ref> | ||
{{FixBunching|beg}} | |||
==References== | |||
{{Infobox mineral | |||
⚫ | < |
||
|name = Annite | |||
|category = mica group, biotite-phlogopite series. The hydorxl analogue of Flourannite | |||
|formula = KFe<sub>3</sub><sup>2+</sup></sup>AlSi<sub>3</sub>O<sub>10</sub> | |||
|molecular weight = 512.88 g | |||
|color = reddish brown | |||
|habit = usually in "blocks" of thin sheets or as aggregations of foliated thin scales. Includes large, well formed pseudohexagonal prisms up to 12cm across and 15cm long.<ref>Hazen, R.M. and C.W. Burnham (1973) The crystal structures | |||
of one-layer phlogopite and annite. Amer. Mineral., 58, 889{900.</ref> | |||
|system = monoclinic, pseudohexagonal | |||
|twinning = contact twins with composition surface on {001} and twin axis {310} | |||
|cleavage = perfect in one direction {001}<ref> Deer, W.A., R.A. Howie, and J. Zussman (1963) Rock-forming minerals, v. 3, sheet silicates, | |||
55{84}. </ref> | |||
|fracture = uneven | |||
|tenacity = flexible<ref> Eugster, H.P. and D.R. Wones (1962) Stability relations of the ferruginous biotite, | |||
annite. J. Petrol., 3, 82{125.</ref> | |||
|mohs = 2.5 - 3 | |||
|luster = submetallic to vitreous; pearly on cleavage surfaces<ref> Dana, E.S. (1892) Dana's system of mineralogy, (6th edition), 634.</ref> | |||
|optical properties = translucent to transparent<ref>Kwak, T.A.P. and P.W. | |||
Askins (1981) Geology and genesis of the F-Sn-W(-Be-Zn) skarn (wrigglite) at Moina, Tasmania. | |||
Econ. Geol., 76, 439{467).</ref> | |||
|streak = brownish white | |||
|gravity = approximately 3.3 g/cm<sup>3</sup> | |||
|density = 3.17g | |||
|other = diagnostic: transparent to subopaque; occurrence: in magnesium poor igneous and metamorphic rocks. | |||
⚫ | </references> | ||
}} | |||
{{FixBunching|mid}} | |||
{{FixBunching|end}} | |||
] | ] |
Revision as of 04:03, 29 September 2010
Annite is a phyllosilicate mineral in the mica family. It has a chemical formula of KFe3AlSi3O10]. Annite is the iron end member of the biotite mica group, the iron rich analogue of magnesium rich phlogopite.
Annite was first described in 1868 for the first noted occurrence in Cape Ann, Rockport, Essex County, Massachusetts, USA and on Pikes Peak, El Paso Co, Colorado. It occurs in igneous and metamorphic rocks that are deficient in magnesium. It occurs associated with fluorite and zircon in the type locality.
Annite | |
---|---|
General | |
Category | mica group, biotite-phlogopite series. The hydorxl analogue of Flourannite |
Formula (repeating unit) | KFe3AlSi3O10 |
Crystal system | monoclinic, pseudohexagonal |
Identification | |
Color | reddish brown |
Crystal habit | usually in "blocks" of thin sheets or as aggregations of foliated thin scales. Includes large, well formed pseudohexagonal prisms up to 12cm across and 15cm long. |
Twinning | contact twins with composition surface on {001} and twin axis {310} |
Cleavage | perfect in one direction {001} |
Fracture | uneven |
Tenacity | flexible |
Mohs scale hardness | 2.5 - 3 |
Luster | submetallic to vitreous; pearly on cleavage surfaces |
Streak | brownish white |
Specific gravity | approximately 3.3 g/cm |
Density | 3.17g |
Other characteristics | diagnostic: transparent to subopaque; occurrence: in magnesium poor igneous and metamorphic rocks. </references> |
Template:FixBunching Template:FixBunching
This article about a specific silicate mineral is a stub. You can help Misplaced Pages by expanding it. |
- ^ Mindat.org
- Deer, W. A., R. A. Howie and J. Zussman, An Introduction to the Rock Forming Minerals, Longman, 1966, p. 212 ISBN 0582442109
- Handbook of Mineralogy
- Hazen, R.M. and C.W. Burnham (1973) The crystal structures of one-layer phlogopite and annite. Amer. Mineral., 58, 889{900.
- Deer, W.A., R.A. Howie, and J. Zussman (1963) Rock-forming minerals, v. 3, sheet silicates, 55{84}.
- Eugster, H.P. and D.R. Wones (1962) Stability relations of the ferruginous biotite, annite. J. Petrol., 3, 82{125.
- Dana, E.S. (1892) Dana's system of mineralogy, (6th edition), 634.
- Kwak, T.A.P. and P.W. Askins (1981) Geology and genesis of the F-Sn-W(-Be-Zn) skarn (wrigglite) at Moina, Tasmania. Econ. Geol., 76, 439{467).