Barytocalcite

Barytocalcite is a relatively rare carbonate mineral with the chemical formula BaCa(CO3)2. It is a double carbonate in which calcium and barium occupy distinct sites within the carbonate lattice, yielding a compound intermediate between baryte and calcite in composition.

Physical properties: Barytocalcite is typically colorless to white, though trace impurities can impart pale yellow to brown hues. It forms tabular to prismatic crystals and irregular grains. The mineral has a vitreous to pearly luster, a white streak, and Mohs hardness around 3. Its specific gravity is relatively high for a carbonate, reflecting its barium content.

Occurrence: It occurs in hydrothermal veins and carbonate-bearing metamorphic and sedimentary rocks. It is commonly found with baryte, calcite, witherite, dolomite, and other carbonate minerals.

Crystal chemistry: Barytocalcite is a calcium–barium carbonate with the formula BaCa(CO3)2. It crystallizes in a calcite-like lattice and shows the characteristic rhombohedral habit of many carbonate minerals.

Name and significance: The name derives from baryta (barium) and calcite (CaCO3). Barytocalcite is primarily of interest to mineralogists and collectors and has no major industrial applications.

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