Jun 12 2014
Adamsite-(y) was named after Frank Dawson Adams, a professor of geology at the McGill University. This mineral has a Mohs scale rating of 3.
Properties of Adamsite-(y)
The following are the key properties of adamsite-(y):
- Cell Data
- Space group: P1
- a = 6.2592(4)
- b = 13.0838(7)
- c = 13.2271(5)
- α = 91.130(1)°
- β = 103.554(1)°
- γ = 90.188(1)°
- Z = 4
- Crystal Data
- Triclinic, pseudo-orthorhombic if twinned
- Point group: 1
- Acicular to fibrous, to 2.5cm
- Elongated along [001], flattened on {001}, showing {010} and {001};
- Spherical radiating groups, which rarely are reticulated
- Twinning: By reflection on {001}, common
- X-ray powder pattern: 12.81 (100), 6.45 (70), 4.456 (60), 4.291 (60), 2.571 (60), 2.050 (50), 2.869 (30)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
| H2O |
29.90 |
31.79 |
| CO2 |
25.10 |
25.89 |
| Y2O3 |
22.88 |
33.21 |
| Na2O |
8.64 |
9.11 |
| Dy2O3 |
3.28 |
- |
| Er2O3 |
2.83 |
- |
| Gd2O3 |
1.92 |
- |
| Nd2O3 |
1.41 |
- |
| Yb2O3 |
1.04 |
- |
| Sm2O3 |
1.02 |
- |
| Ho2O3 |
0.90 |
- |
| Tb2O3 |
0.56 |
- |
| Ce2O3 |
0.37 |
- |
| Tm2O3 |
0.27 |
- |
| CaO |
0.05 |
- |
| Total |
100.17 |
100.00 |
- Optical Properties
- Transparent to translucent
- Optical class: Biaxial (+)
- Pleochroism: In pale colors if cuprian or cobaltian
- Orientation: Y = b; Z^a = 14°
- α = 1.480(4); β = 1.498(2); γ = 1.571(4)
- 2V(meas.) = 53(3)°
- 2V(calc.) = 55°
- Estimated Properties
| Electron density |
Bulk density (electron density) = 2.16 g/cm3
note: Specific gravity of adamsite-(y) = 2.18 g/cm3 |
| Photoelectric |
PEAdamsite-(y) = 87.57 barns/electron
U = PEAdamsite-(y) x ρelectron density = 189.50 barns/cm3 |
| Fermion index |
Fermion index = 0.03
Boson index = 0.97 |
Radioactivity
|
Adamsite-(y) is radioactive
|
How to Identify Adamsite-(y)
Adamsite-(y) can be identified in the field by its color variations, such as white, pale pink, and pale purple. It is sometimes even colorless. It is translucent to transparent, with brittle fracture and spherical, rounded aggregates. It has {001} perfect, {100} good, {010} good cleavage. This mineral has a vitreous, pearly luster, with a white streak.
The hardness of adamsite-(y) is 3 – approximate to calcite.
Global Distribution
Adamsite-(y) is distributed in the following places:
- Canada - From Mont Saint-Hilaire, Quebec
- Norway – Nordland, Tysfjord, Hundholmen
- Russia - Northern region, Kola Peninsula, Lovozero Massif, Alluaiv Mt, Umbozero mine, Shomiokitovoe pegmatite
Occurrence of Adamsite-(y) and Useful Mineral Association
Adamsite-(y) occurs in a rare late-stage, low-temperature hydrothermal mineral in an alkalic pegmatite dike, associated with an intrusive alkalic gabbro-syenite complex.
It is often associated with minerals such as thomasclarkite-(Y), donnayite-(Y), petersenite-(Ce), horvathite-(Y), and rhodochrosite.
References