Brucite

You may be familiar with the bright yellow brucites that are currently coming out of India, but how about blue brucite that once came from Canada? This specimen showcases beautiful, platy blue cleavages of brucite, the mineral form of magnesium hydroxide with the chemical formula Mg(OH)₂. Brucite commonly forms as an alteration product of periclase in marble, often occurring in foliated masses or as thin, tabular crystals.

This specimen originates from the Malone Quarries in Marmora, Ontario, a locality that once consisted of six small quarries. These quarries produced a variety of notable mineral specimens, including brucite, dolomite, and calcite. Although the Malone Quarries are now overgrown and inactive, the fine brucite specimens that once came out are now treasured by collectors for their beauty and rarity.