Chemistry:Xiangjiangite

Xiangjiangite
General
Category	Phosphate minerals
Formula (repeating unit)	(Fe3+, Al)(UO2)4(PO4)2(SO4)2(OH)·22(H2O)
Strunz classification	8.EB.05
Crystal system	Tetragonal Unknown space group
Unit cell	1,142.31
Identification
Formula mass	453.91 g/mol
Color	Yellow
Crystal habit	Microscopic crystals; Platy
Mohs scale hardness	1–2
|re|er}}	Silky
Streak	Light yellow
Diaphaneity	Semitransparent
Specific gravity	3.47
Optical properties	Biaxial(−)
Refractive index	nα = 1.558 nβ = 1.576 nγ = 1.593
Birefringence	0.035
Pleochroism	Weak
2V angle	87
Dispersion	Weak
Other characteristics	Radioactive
References

Xiangjiangite is a phosphate mineral discovered near and named for the Xiang Jiang River in China . It was approved by the IMA in 1978, and was named after its locality.

Properties

Xiangjiangite is a pleochroic mineral, which is an optical phenomenon, meaning that depending on the axis it is viewed on, it appears as it changes colors. On both the X and Y axis, it can be seen in a yellow color, while on the Z axis it appears to be weak yellow color. This mineral is very strongly radioactive, and has a 3,845,084.01 radioactivity measured in GRapi.

It mainly consists of uranium (49.67%) and oxygen (39.23%), but otherwise contains sulphur (3.35%), phosphorus (3.23%), hydrogen (2.37%), iron (1.46%) and aluminum (0.70%).