AM-2018-10014-A · Tourmaline (schorl)unverified
The classification below is preliminary. Spectroscopic confirmation is incomplete; values shown reflect the most recent analytical pass and may be revised without notice.
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) | 3.10 |
| colour | Black with greenish termination |
| type locality | Schwarzwald, Baden-Württemberg, Germany |
raman spectroscopy532 nm · pass A
reported peaks (cm⁻¹): 221, 365, 709, 1062
notessubmitter remarks + registry
Donated as part of a decommissioned teaching collection; no individual provenance retained.