Trona

Trona is a non-marine evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in... Wikipedia

• Category:  Carbonate mineral
• Formula, (repeating unit):  Na 2CO 3·NaHCO 3·2H 2O
• Strunz classification:  5.CB.15
• Crystal system:  Monoclinic
• Crystal class:  Prismatic (2/m), (same H-M symbol)
• Space group:  C2/c (no. 15)
• Color:  Colorless (in transmitted light) or white, grey-white, also grey to yellowish grey, light yellow
• Crystal habit:  Columnar, fibrous and massive.
• Cleavage:  perfect, and indistinct
• Fracture:  Brittle – subconchoidal
• Mohs scale hardness:  2.5
• Luster:  Vitreous
• Streak:  White
• Diaphaneity:  Translucent
• Specific gravity:  2.11–2.17
• Optical properties:  Biaxial (−)
• Refractive index:  nα
• Birefringence:  δ
• Solubility:  Soluble in water
• Other characteristics:  May fluoresce under short wavelength ultraviolet
• Data source:  DuckDuckGo