Glendonites: Enigmatic Mineral Pseudomorphs and Their Ephemeral Precursor

Abstract

At room temperatures, water is released, effecting dramatic changes (B) in the appearance and structural integrity of the crystals. The remaining pseudomorphs (glendonites) are composed of a mass of minute crystals of calcium carbonate, most likely calcite, but possibly also vaterite. Unmeasured specimens were 2–3 cm in length. John DeLeon photos.