AM-2017-10014-A · Tourmaline (schorl)archived
physical & structuralrev. 3
| designation | Tourmaline (schorl) |
|---|---|
| chemical formula | NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄ |
| classification | Cyclosilicate / Tourmaline group |
| crystal system | Trigonal |
| mohs hardness | 7 – 7.5 |
| density (g/cm³) | 3.14 |
| colour | Black with greenish termination |
| type locality | Dzhezkazgan, Karaganda, Kazakhstan |
raman spectroscopy532 nm · pass A
reported peaks (cm⁻¹): 220, 713, 1063
notessubmitter remarks + registry
Donated as part of a private estate; no individual provenance retained.