Hoidmine

Hoidmine is a rare mineral species categorized as a rare-earth–bearing silicate. It was first described from the Hoid Basin and is named for the locality that yielded the type specimens.

The mineral was identified in late 20th-century fieldwork in pegmatitic veins within metamorphosed granitic rocks. It occurs in veinlets and pockets within coarse pegmatites and is commonly found alongside quartz, muscovite, fluorite, and other rare-earth minerals.

Hoidmine crystals are pale greenish-blue to green, typically prismatic or tabular, with a vitreous to adamantine luster. It has a Mohs hardness near 6.5 to 7 and a pale-green streak. The mineral's crystal system is monoclinic. The composition is rich in holmium and other rare-earth elements, with minor amounts of iron and titanium.

Geologically, hoidmine is believed to crystallize from late-stage magmatic differentiation in pegmatites, where high concentrations of rare-earth elements can accumulate. It forms under relatively low-temperature conditions compared with early-formed minerals.

In terms of use, hoidmine has limited industrial applications due to its rarity but holds interest for collectors and researchers. The holmium content makes it relevant to studies of rare-earth mineralogy and pegmatite genesis, rather than as a practical ore source.