Jun 11 2014
Iimoriite-(Y) was first discovered in 1970, from the Fusamata and Suishoyama, Kawatamachi, Kyoto Prefecture, Japan.
It was named after Satoyasa Iimorii, a Japanese mineralogist who first described the mineral, and also for the presence of yttrium in its composition.
Properties of Iimoriite-(Y)
The following are the key properties of Iimoriite-(Y):
- Cell Data
- Space Group: P1
- a = 6.573(1)
- b = 6.651(1)
- c = 6.454(1)
- α = 116.44°
- β = 92.34°
- γ = 95.6°
- Z = 2
- Crystal Data
- Triclinic
- Point Group: 1
- As masses up to 3cm
- X-ray Powder Pattern: 2.881 (100), 2.954 (80), 2.784 (40), 3.023 (36), 2.841 (35), 2.705 (29), 3.20 (27)
- Chemical Composition
| Elements |
Content |
| Y2O3 |
45.7 |
| RE2O3 |
22.8 |
| SiO2 |
19 |
| CO2 |
11.3 |
| Fe2O3 |
0.4 |
| H2O+ |
0.39 |
| P2O5 |
<0.2 |
| CaO |
0.1 |
| H2O- |
0.1 |
| TiO2 |
0.05 |
| MnO |
0.01 |
| Total |
99.85 |
- Optical Properties
- Optical Class: Biaxial (-)
- α = 1.75-1.79
- β = 1.82-1.83
- γ = 1.83
- 2V(meas.) = 31°
- 2V(calc.) = 31.5°
- Estimated Properties
| Electron density |
Bulk density (electron density) = 4.09 g/cm3
note: Specific gravity of Iimoriite-(Y) = 4.38 g/cm3 |
| Photoelectric |
PEIimoriite-(Y) = 68.13 barns/electron
U = PEIimoriite-(Y) x ρElectron density = 278.61 barns/cm3 |
| Fermion index |
Fermion index = 0.004
Boson index = 0.995 |
Radioactivity
|
Iimoriite-(Y) is not radioactive
|
How to Identify Iimoriite-(Y)
Iimoriite-(Y) is either colorless, or occurs in purple-gray, gray-pink, white, or brown colors. It has a white streak, distinct cleavage, and vitreous luster.
The hardness range of Iimoriite-(Y) is between 5 and 5.6, and the density of Iimoriite-(Y) is 4.47 g/cm3.
Global Distribution
Iimoriite-(Y) is distributed in the following places:
- Fusamata and Suishoyama, Fukushima Prefecture, and Soraku, Kyoto Prefecture, Japan
- I and L No. 4 claim, Bokan Mountain, Prince of Wales Island, Alaska, USA
- Trimouns talc deposit, 6km north-east of Luzenac, Ariµege, France
Occurrence of Iimoriite-(Y) and Useful Mineral Association
Iimoriite-(Y) occurs in quartz-microcline pegmatites, and veins of peralkalic riebeckite-aegirine granite.
It is closely associated with zircon, galena, sphalerite, pyrite, fluorite, siderite, albite, quartz, thalenite, uraninite, fergusonite, monazite, and biotite.
References