May 10 2013
Tinaksite was first discovered in 1965 from Murun alkalic massif, near Olekminsk, Yakutia, Russia. It was named after the presence of titanium, sodium, potassium and silicon in its composition.
Properties of Tinaksite
The following are the key properties of tinaksite:
- Cell Data
- Space Group: P1
- a = 10.377(3)
- b = 12.166(3)
- c = 7.059(1)
- α = 90:91(1)°
- β = 99:3(1)°
- γ = 92:76(3)°
- Z = 2
- Crystal Data
- Triclinic
- Point Group: 1
- As well-formed long prismatic crystals, to 15 cm; commonly as bundles and rosettes of radiating crystals, or compact fibrous aggregates, to 10 cm
- X-ray Powder Pattern: 3.03 (100), 3.25 (80), 2.331 (55), 3.09 (50), 2.952 (50), 2.865 (50), 2.674 (45)
- Chemical Composition
| Elements |
Content 1 |
| SiO2 |
55.82 |
| CaO |
14.20 |
| K2O |
12.55 |
| TiO2 |
10.12 |
| Na2O |
4.30 |
| H2O+ |
1.20 |
| FeO |
0.92 |
| Fe2O3 |
0.91 |
| MnO |
0.40 |
| H2O- |
0.08 |
| MgO |
0.04 |
| Al2O3 |
trace |
| Total |
100.54 |
- Optical Properties
- Optical Class: Biaxial (+)
- Pleochroism: X = Y = colorless; Z = pale orange-brown.
- Orientation: X’ ^ {010} = 1°- 4°; Y ^ {010} = 16°-18°
- Dispersion: Strong
- α = 1.593-1.599
- β = 1.621-1.627
- γ = 1.666-1.673
- 2V(meas.) = 68°-78°
- Estimated Properties
| Electron density |
Bulk density (electron density)=2.79 g/cm3
note: Specific gravity of Tinaksite =2.82 g/cm3 |
| Photoelectric |
PETinaksite = 4.91 barns/electron
U= PETinaksite x ρElectron density= 13.70 barns/cm3 |
| Fermion index |
Fermion index = 0.01
Boson index = 0.99 |
Radioactivity
|
Tinaksite is barely detectable
|
How to Identify Tinaksite
Tinaksite occurs in light brown, pale yellow or pink color. It has a perfect cleavage, transparent to translucent appearance, vitreous luster and white streak. It can be formed as prismatic, fibrous or radial crystals. The mineral has a relative hardness of 6 and density of 2.82 g/cm3.
Global Distribution
Tinaksite is distributed in the following places:
- Murun massif, southwest of Olekminsk, Yakutia, Russia
- Mt. Rasvumchorr, Khibiny massif, Kola Peninsula.
Occurrence of Tinaksite and Useful Mineral Association
Tinaksite occurs as an accessory mineral in potassic feldspar metasomatites at the contact with limestones. It is closely associated with hisingerite, astrophyllite, aegirine, pyroxene, orthoclase, xonotlite, canasite, quartz, and potassic feldspar.
References