Formula: (V,Fe,Fe,Ti)10O14(OH)2
Origin of name: or Thomas Brennan Nolan (1901-1992), formerly Director of the U. S. Geological Survey, Washington, D.C., USA.
Crystal system: Hexagonal
Crystal class: 6mm
Twinning:
Unit cell: a = 5.846, c = 9.254
Colour: Black
Diaphaneity: Opaque, slightly translucent in thin fragments
Luster: Submetallic
Habit: Hexagonal plates to 1 mm, subhedral to euhedral, radiating crusts, as exsolution lamellae in vanadian magnetite
Hardness: 5 to 5.5
Specific gravity: 4.69
Cleavage: None
Tenacity: Uneven fracture
Streak: Brownish black
Synonyms/varieties:
Comments:
| Back to Alphabetical list | Colour photos | Optical properties/Thin sections | SEM images | TEM images | vibrational spectra description | IR spectra | Raman spectra | N-IR spectra | F-IR spectra | IES spectra |