From Surf Wiki (app.surf) — the open knowledge base

Zaïrite

Field	Value
name	Zaïrite
category	Phosphate minerals
image	Zairite-520947.jpg
imagesize	260px
caption	Zaïrite from Eta-Etu, Kivu, Democratic Republic of Congo (Zaïre), (field of view 6 mm)
formula	Bi(Fe3+,Al)3[(OH)6	(PO4)2]
IMAsymbol	Zaï
molweight	646.86 g/mol
strunz	8.BL.13
system	Trigonal
class	Hexagonal scalenohedral (m)
H-M symbol: ( 2/m)
symmetry	Rm
unit cell	a = 7.015, c = 16.365 [Å]; Z = 3
color	Greenish, greenish white, yellow green.
cleavage	None observed
fracture	Irregular, uneven
tenacity	Brittle
mohs	4.5
luster	Vitreous, resinous
refractive	nω = 1.820 - 1.830 nε = 1.810
opticalprop	Uniaxial(-)
birefringence	δ = 0.0100-0.0200
streak	White
gravity	4.37
diaphaneity	Transparent to translucent
other	Occurrence: Rare mineral in the weathering zone of quartz wolframite deposits
references

H-M symbol: ( 2/m)

Zaïrite is a phosphate mineral with the chemical formula Bi(Fe3+,Al)3[(OH)6|(PO4)2]. The name was given from where it was locally discovered in Eta-Etu, Kivu, Congo (Zaïre) in 1975.

Properties

Zaïrite crystallizes in the trigonal crystal system, which means it contains three equal horizontal axes with angles of 120° between them. The mineral has a trigonal-hexagonal scalenohedron shape. Zairite belongs to the uniaxial optical class. It means the light and vibrations passing through the mineral only has one direction it follows and it travels at the same speed.

Occurrence

The mineral was first described from the Eta-Etu district, northern Kivu Province, Democratic Republic of the Congo (then Zaire) usually in the weathering areas of quartz wolframite deposits where it occurs with native bismuth, bismutite, quartz and mica. Zaïrite is found in granite pegmatites, which are igneous coarse-grained rocks. It has also been reported from Kreuzberg Mountain in Upper Palatinate, Bavaria, Germany.

References

Warr, L.N.. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine.
[http://www.mindat.org/min-4382.html Mindat.org]
[http://webmineral.com/data/Zairite.shtml Webmineral data]
[http://rruff.geo.arizona.edu/doclib/hom/zairite.pdf Handbook of Mineralogy]
Klein, C., Dutrow, B. (2007) The 23rd edition of the Manual of Mineral Science, 131 p. John Wiley and Sons, Inc. Hoboken, New Jersey, U.S.A.
McKie, D., McKie, C. (1986) Essentials of Crystallography. III. Blackwell Scientific Publishers, p.69

Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

aluminium-minerals bismuth-minerals iron(iii)-minerals phosphate-minerals trigonal-minerals minerals-in-space-group-166 crandallite-group

Want to explore this topic further?

Ask Mako anything about Zaïrite — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report