atlassten

atlassten is a rare mineral reported in high-grade metamorphic terranes in the Atlas region. The name derives from the Atlas mountains and the German word stein, meaning stone. It is described as a dense, opaque mineral with a metallic to submetallic luster and a conchoidal fracture.

Physical properties of atlassten include a color range from steel gray to dark bronze, a hardness estimated around 6 to 7 on the Mohs scale, and a density of roughly 4.8 to 5.2 g/cm3. It is opaque, with a metallic to submetallic sheen, and typically shows a lack of conspicuous cleavage, instead fracturing conchoidally. The mineral has a weak to moderate magnetic susceptibility in hand samples.

Occurrence and formation are weakly constrained due to the rarity of specimens. Atlassten crystals have been found in small pockets within contact-metamorphosed ultramafic rocks near the Atlas mountains, often in association with magnetite, olivine, pyroxene, and garnet. It is thought to form under high-temperature, high-pressure conditions associated with subduction-zone metamorphism, though the exact stabilization mechanisms are not well established.

Chemistry and structure place atlassten in the category of complex iron-magnesium silicates with trace aluminum and titanium. It is described as crystallizing in a hexagonal or pseudo-hexagonal system, with a microstructure that includes layered sheets which may contribute to its mechanical properties.

Applications and mining for atlassten are presently limited by its scarcity. There is no large-scale industrial use, but the mineral attracts interest from researchers studying high-pressure metamorphism and mineral stability. Small specimens are valued by collectors and incorporated into mineralogical surveys and museum collections.