A carbonate mineral, strontium
carbonate (SrCO3). It has orthorhombic system, hexagonal twinned
crystals, and it also occurs as massive or columnar aggregates. It can be
pale green, white, gray, yellow, or brown. Strontianite is found in low-temperature
hydrothermal veins, often in limestone.
Hardness 3.5–4; relative density 3.7.
AND PLANETARY SCIENCE