Jouravskite on Xonotlite

Jouravskite – Ca3Mn4+(SO4)(CO3)(OH)6·12H2O
Class: Sulfates
Crystal System: Hexagonal
Hardness: 2.5
Calcite
Talc (1)Diamond (10)
Soft. A fingernail can scratch it.
Xonotlite – Ca6Si6O17(OH)2
Class: Silicates – Inosilicates
Crystal System: Monoclinic
Hardness: 6 - 6.5
Orthoclase
Talc (1)Diamond (10)
Scratches glass. Harder than a steel knife.
Origin: N’Chwaning III Mine - N’Chwaning Mines, Kuruman, Kalahari manganese field, Northern Cape – South Africa
Did you know?

Nearly half of jouravskite is water. About 42 percent of its weight is water locked inside the crystal itself, which leaves it startlingly light: a density near 1.9, where most minerals run three times that of water or more. In the hand it feels wrong, too light for a stone.

Xonotlite is one of the few minerals industry decided to make rather than mine. Grown in vessels of hot lime and water, its interlocking needles turn into board that shrugs off heat, so much of the xonotlite in use today was never underground at all.