Oct 21 2013
Carbocernaite was named after the key chemical components -CARBOnate, CERium, and NAtrium (sodium).
Properties of Carbocernaite
The following are the key properties of carbocernaite:
- Cell Data
- Space group: Pb2m
- a = 6.430
- b = 7.301
- c = 5.214
- Z = 2
- Crystal Data
- Orthorhombic
- Point group: mm2
- As tabular crystals with wedge-like terminations, to 4 mm, with dominant {100}, minor {010}, {001}, {021}, {540}, {210}, vicinal {305} and {210}
- as grains and exsolution lamellae
- X-ray powder pattern: 3.00 (10), 2.015 (9), 1.813 (8), 2.60 (7b), 2.29 (7b), 3.66 (5), 2.082 (5)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
| CO2 |
33.85 |
[32.02] |
| SrO |
17.77 |
18.74 |
| CaO |
16.68 |
17.15 |
| La2O3 |
8.78 |
13.26 |
| Ce2O3 |
10.27 |
10.16 |
| BaO |
5.24 |
1.64 |
| Na2O |
3.15 |
3.83 |
| Nd2O3 |
2.47 |
1.82 |
| H2O |
1.22 |
- |
| Pr6O11 |
0.99 |
0.76 |
| MnO |
- |
0.69 |
| FeO |
0.53 |
- |
| Gd2O3 |
0.39 |
- |
| Sm2O3 |
0.30 |
0.31 |
| Total |
101.64 |
[100.38] |
- Optical Properties
- Optical Class: Biaxial (–)
- Orientation: X = b; Y = a; z = c
- Dispersion: r > v, marked
- α = 1.569(2); β = 1.679(2); γ = 1.708(2)
- 2V(meas.) = n.d.
- 2V(calc.) = 52?
- Estimated Properties
| Electron density |
Bulk density (electron density) = 3.39 g/cm3
note: Specific gravity of carbocernaite = 3.62 g/cm3 |
| Photoelectric |
PECarbocernaite = 124.93 barns/electron
U=PECarbocernaite x ρ electron density = 423.03 barns/cm3 |
| Fermion index |
Fermion index = 0.02
Boson index = 0.98 |
| Radioactivity |
Carbocernaite is radioactive |
How to Identify Carbocernaite
Carbocernaite can be identified in the field by its color variations such as brown, yellow, yellow brown and white. It is sometimes colorless. Its transparent to translucent form has {100} indistinct, {021} indistinct, {010} indistinct cleavage.
This mineral has a vitreous - greasy luster with white streak. The fracture on this mineral is brittle. The density of carbocernaite is 3.53 g/cm3 with a hardness of 3 – approximate to calcite.
Global Distribution
Carbocernaite is distributed in the following places:
- Russia - From the Vuoriyarvi carbonatite complex and in the Khibiny massif, Kola Peninsula; at the Ozernyi carbonatite, southeastern Sakha
- Afghanistan - At the Khanneshin carbonatite complex
- China - In the Bayan Obo Fe–Nb–RE deposit, 130 km north of Baotou, Inner
- Mongolia, and at Weishan, Shandong Province
- Vietnam -From the Phan Si Pan Range
- India - At the Sarnu-Dandali alkaline complex, Barmer District, Rajasthan,
- Canada - Ontario, Mont Saint-Hilaire, Quebec.
Occurrence of Carbocernaite and Useful Mineral Association
Carbocernaite typically occurs in an uncommon accessory mineral in dolomite–calcite carbonatite associated with an alkaline ultramafic massif; exsolved from calcite and in a carbonatite dike in fenitized melanephelinite.
It is often associated with minerals such as chlorite, ankerite, alstonite, anatase, quartz, dolomite, barite, mckelveyite-(Y), calkinsite-(Ce) and khanneshite.
References