Alkurarvo

Alkurarvo is a rare mineral described in contemporary mineralogy as a metallic sulfide-oxide that forms layered crystals. It has drawn attention for its distinctive iridescent tarnish and compact prismatic habit.

It crystallizes in the monoclinic system; hardness 5.5–6 on the Mohs scale; color steel-gray with blue-green iridescence; luster metallic; density around 4.8 g/cm3; composition roughly iron- and nickel-rich with trace copper, and an idealized chemical interpretation that includes sulfide layers interleaved with oxide-like sheets.

Found in hydrothermal veins within contact metamorphic zones of the Alkura Basin; associated minerals include magnetite, pyrite, and sphalerite; it forms under high-temperature, low-sulfur conditions that promote layered stacking of metal-sulfide and oxide-rich domains.

Named in 1998 by Dr. A. K. Rova, the name alkurarvo derives from the Alkura region and a local term meaning layered, in reference to its stacked crystal habit. Alkurarvo is of interest for insights into sulfide-oxide layering in hydrothermal systems. At present it is extremely scarce and not of economic importance, but it has value to researchers studying mineralogical processes and phase relations in sulfide-oxide assemblages.