strontianite

Strontianite is a mineral that consists of strontium carbonate, SrCO3. It is the primary carbonate form of strontium and a source of the element in mineral deposits. It was first described from Strontian, Scotland, and its name is derived from that locality.

Strontianite forms in hydrothermal veins and in carbonate rocks such as limestones and dolostones, often together with calcite, dolomite, celestine (SrSO4), witherite (BaCO3), and other carbonates. It can occur as colorless to white or gray prismatic crystals as well as massive aggregates.

Strontianite crystallizes in the orthorhombic system. It has a vitreous luster and is transparent to translucent. Its color is typically colorless or white, sometimes yellowish or gray due to impurities. It has a Mohs hardness of about 3 and is relatively soft; it effervesces with acids.

Uses: Strontianite is a source of strontium; it can be processed to produce strontium compounds used in glass, ceramics, pyrotechnics, and electronics. However, celestine is generally the more important ore of strontium.

Occurrences: Besides Strontian, Scotland, strontianite is found in various carbonate-rock settings worldwide, often in hydrothermal veins and replacement zones, and is commonly associated with calcite, dolomite, and celestine.