Tinaksite

Formula: K2Na(Ca,Mn)2TiSi7O19(OH)

Origin of name: combination of symbols for some of the elements in its composition (Ti, Na, K)

 

Crystal system: Triclinic

Crystal class: 1

Twinning:

Unit cell: a = 10.35, b = 12.17, c = 7.05, α = 91°, β = 99.333°, γ = 92.5°

 

Colour: Pink, pale yellow, light brown

Diaphaneity: Transparent to translucent

Luster: Vitreous on cleavage

Habit: Crystals prismatic, to several cm, in rosettes and radiating fibrous aggregates

Hardness: 6

Specific gravity: 2.85

Cleavage: 2; {010} perfect, {110} imperfect, (010) (110) = 131.5°

Tenacity: 

Streak: White

 

Synonyms/varieties:

 

Comments:  Found in K-feldspar metasomatites in contact with limestone.

 

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