public catalogue · open access · last index pass 2026-05-08 08:14:02 UTChost: cat-pub-04 · build 0.14.3-prototype · rev rA9F2
overviewcatalogueAM-2015-02208-C

AM-2015-02208-C · Tourmaline (schorl)archived

physical & structuralrev. 1
designationTourmaline (schorl)
chemical formulaNaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄
classificationCyclosilicate / Tourmaline group
crystal systemTrigonal
mohs hardness7 – 7.5
density (g/cm³)3.18
colourBlack
type localityErongo Mountains, Namibia
raman spectroscopy532 nm · pass C
200400600800100012001400Raman shift (cm⁻¹)intensity (arb.)2203657111063
λ_excitation: 532 nm · acq. 3 × 10 s · grating 1800 g/mmfig. 1 · raman.am-2015-02208-c.svg

reported peaks (cm⁻¹): 220, 365, 711, 1063

notessubmitter remarks + registry

Prismatic crystals with striated faces.