Meionite
Ca4Al6Si6O24(CO3)IMA symbol: Megrandfathered
Meionite is a silicate mineral with the formula Ca4Al6Si6O24(CO3). It has a Mohs hardness of 5.5-6, typically colorless or white in color, with a vitreous luster, a specific gravity of 2. Its streak is white; cleavage is perfect.
Photos
.jpg){kind=link}
Crystallography
| Space group | I 4/m |
|---|---|
| Cell (Å, °) | a = 12.16711, b = 12.16711, c = 7.575466; α = 90, β = 90, γ = 90 |
| Cell volume | 1121.46 ų, Z = 2 |
| Axial ratios | 1.0000:1:0.6226calculated from COD 9010507 |
| Source structure | COD 9010507 (American Mineralogist, 2008) — 1 of 17 structures |
Powder X-ray diffraction (calculated)
| d (Å) | 3.467 | 3.083 | 2.699 | 3.042 | 3.848 | 1.375 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 81.8 | 46.9 | 36.1 | 28.4 | 19.6 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9010507; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 2.743 g/cm³calculated from COD 9010507 |
|---|---|
| Hardness (Mohs) | 5.5-6single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 2 g/cm3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Color | colorless, whitesingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | whitesingle sourceWikidata (CC0) |
| Luster | vitreousDana, System of Mineralogy, 6th ed. (1892) |
| Cleavage | perfectDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 934.71 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Ca 17.15%, Al 17.32%, Si 18.03%, O 46.22%, C 1.28% |
Classification
| Nickel-Strunz (10th) | 9.FB.15Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 9.FB.15Wikidata (CC0) |