Kermesite

Formula: Sb2S2O

Reflected/transmitted colour: polished section gray

Pleochroism:

Optical isotropy/anisotropy: biaxial, polished section strong to extreme anisotropy, violet to blue-green (in oil masked by internal reflections)

Optical sign: +

Refractive indices: α ≥ 2.72, β ≥ 2.72, γ ≥ 2.72

Birefringence δ/bireflectance: polished section distinct, gray to brownish or greenish gray

2V angle:

Dispersion:

Optical orientation: γ = y = elongation

Optical axial plane:

 

Back to Alphabetical list Colour photos Physical, chemical and crystallographic description SEM images TEM images vibrational spectra description IR spectra Raman spectra N-IR spectra F-IR spectra IES spectra