AM-2012-10004-A · Chalcedonyarchived
physical & structuralrev. 3
| designation | Chalcedony |
|---|---|
| chemical formula | SiO₂ |
| classification | Tectosilicate / cryptocrystalline quartz |
| crystal system | Trigonal |
| mohs hardness | 6.5 – 7 |
| density (g/cm³) | 2.61 |
| colour | Banded grey |
| type locality | N'Chwaning II mine, Northern Cape, South Africa |
raman spectroscopy532 nm · pass A
reported peaks (cm⁻¹): 204, 462, 501, 1066
notessubmitter remarks + registry
Macroscopic appearance consistent with chalcedony; no surface alteration observed at the time of intake.