Scapolite

Scapolite – (Na,Ca)4(Al,Si)12O24(Cl,CO3)
Class: Silicates – Tectosilicates (Scapolite Group)
Crystal System: Tetragonal
Hardness: 5-6
Orthoclase
Talc (1)Diamond (10)
About as hard as a steel knife blade.
Origin: Merelani Hills Manyara Region – Tanzania
Did you know?

Scapolite is one of the few minerals spotted on Mars from Earth. In the late 1980s, infrared readings of regions like Hellas and Chryse matched its signature, and because that signal came from carbonate and sulfate ions locked in the crystal, it hinted that briny, salt-rich water once worked the Martian surface.