strontianite Mineral, SrCO₃; sp. gr. 3.7; hardness 3.5–4.0; orthorhombic; white to pale green, grey, or pale yellow; white streak; vitreous lustre; crystals prismatic or acicular, but also fibrous and massive; cleavage prismatic, good {110}; occurs in low-temperature hydrothermal veins, often in limestone, and in association with celestite, barite, and calcite; soluble, with effervescence, in dilute hydrochloric acid. It is named after the type locality of Strontian, Highland Region, Scotland.

strontianite Carbonate mineral, strontium carbonate (SrCO₃). It has an orthorhombic system, massive or columnar aggregates, or hexagonal twinned crystals. It can be pale green, white, grey, yellow, or brown. It is found in veins, often in limestone. Hardness 3.5–4; r.d. 3.7.