May 16 2013
Sicklerite is present only as an alteration product of Triphylite and Lithiophilite and occurs commonly as rims around partly altered masses or crystals of the latter species.
Chemical Formula – LiMn2+0.75Fe2+0.25(PO4)
Properties of Sicklerite
The following are the key properties of Sicklerite
- Cell Data
- Space Group: Pmnb
- a = 6.030
- b = 10.082
- c = 4.750
- Z = 4
- Crystal Data
- Orthorhombic
- Point Group: 2/m 2/m 2/m
- Massive, as rims around and in crystals and masses of triphylite-lithiophilite
- X-ray powder pattern: 2.971 (100), 2.495 (75), 3.497 (40), 2.448 (35), 5.037 (30), 4.327 (30), 1.6081 (25)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
| V2O5 |
43.10 |
46.68 |
| Fe2O3 |
11.26 |
8.06 |
| Mn2O3 |
2.10 |
2.47 |
| MnO |
33.60 |
37.12 |
| CaO |
0.20 |
0.12 |
| (LiH)2O |
3.80 |
[7.85] |
| Na2O |
|
0.13 |
| K2O |
|
0.04 |
| H2O |
1.71 |
n.d |
| Insol. |
4.18 |
| Total |
99.95 |
[100.00] |
- Optical Properties
- Optical Class: Biaxial (-)
- α= 1.710–1.720 β= 1.730–1.738 γ= 1.745
- Estimated Properties
| Electron density |
Bulk density (electron density)= 3.49 g/cm3
note: Specific gravity of sicklerite=3.64 g/cm3 |
| Photoelectric |
PESicklerite = 10.44 barns/electron
U=PESicklerite x ρElectron Density= 36.41 barns/cc. |
| Fermion index |
Fermion Index = 0.0053940389
Boson Index = 0.9946059611 |
| Radioactivity |
Sicklerite is not radioactive |
How to Identify Sicklerite
Sicklerite is subtranslucent to opaque. It has a yellow to red brown color, black or yellow brown in the thin section.
Global Distribution
Sickleriteis distributed in the following places:
- In the USA, in the Vanderburg mine, Hiriart Mountain, and the Stewart mine, Pala district, San Diego Co., California; from the White Picacho district, Yavapai Co., Arizona;
- In the Custer Mountain mine, 2.5 km east-southeast of Custer, Custer Co., South Dakota.
- From the Tanco pegmatite, Bernic Lake, Manitoba, Canada. At Tammela, and in the Viitaniemi pegmatite near Erajarvi, Finland.
- From Varutrask, at the Norr pegmatite, on Rano Island, and on Uto Island, Sweden. From Sidi-bou-Othmane, Morocco. Occurs at Wodgina, Western Australia.
- Is also present in many other pegmatites; chemical analyses are needed to confirm that the material fits the present definition.
Occurrence of Sicklerite and Useful Mineral Association
Sicklerite is formed by late hydrothermal weathering or alteration of triphylite-lithiophilite in complex zoned granite pegmatites and is associated with the minerals Hureaulite, stewartite, jahnsite, phosphosiderite.
References