Marble

This specimen is marble, a metamorphic rock formed when limestone is subjected to heat and pressure deep within the Earth. The original calcite crystals recrystallise, producing the dense, interlocking texture visible in this piece. The specimen is predominantly white to pale grey, with subtle variations caused by trace minerals and impurities present during metamorphism. Marble is composed mainly of the mineral calcite (calcium carbonate), which gives it its characteristic softness relative to many silicate rocks and its ability to take a polish. In this specimen, the granular crystalline texture is clearly visible, typical of New Zealand marbles from the Takaka area.