Definitions

1. noun

A manganese carbonate mineral, MnCO3, often found in hydrothermal veins and as a secondary mineral in manganese ore.

“The geologist collected a sample of proustite for further analysis.”

2. noun

A rare and highly unstable mineral, named after the French novelist Marcel Proust.

“The mineralogist was thrilled to have discovered a proustite in the remote region.”