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.
chain of custody8 events · 5 seal-breaks
Events recorded against this accession in the registry's printed custody book. Operator initials are anonymous. Storage codes follow the convention vault-shelf-drawer.
| timestamp | stage | detail | op. |
|---|---|---|---|
| 2012-06-12 16:26 UTC | intake | weighed, dimensioned, photographed; container sealed and labelled with the accession identifier | M.A. |
| 2012-06-13 13:59 UTC | pass A | visual inspection · density (Archimedes) · mass to ±0.01 g | V.O. |
| 2012-06-25 11:10 UTC | pass B | Raman acquisition; 4 peaks above prominence threshold instrument: Renishaw inVia (532 nm) ref. checked: ICDD card 04-8701 | V.O. |
| 2012-06-27 08:49 UTC | storage | re-bagged, label re-printed; placed in vault D, shelf 04, drawer 18 | M.A. |
| 2014-06-27 11:58 UTC | re-inspection | seal intact · label legible · no visible degradation | V.O. |
| 2016-06-26 14:09 UTC | re-inspection | seal intact · label legible · no visible degradation | V.O. |
| 2018-06-26 16:12 UTC | re-inspection | seal intact · label legible · no visible degradation | V.O. |
| 2020-06-25 13:58 UTC | re-inspection | seal intact · label legible · no visible degradation | V.O. |
physical location: vault D · shelf 04 · drawer 18 · last documented inspection: 2020-06-25 13:58 UTC