![19.0 Carbonatite. Calcite (?) and minor alkali amphiboles constitute this rock. Other possible carbonate minerals are ankerite and dolomite. This sample courtesy of Sonoma State University Geology Department. [Scale is standard GSA scale with cm divisions.]](../19.0.JPG)
19.0 Carbonatite. Calcite (?) and minor alkali amphiboles constitute this rock. Other possible carbonate minerals are ankerite and dolomite. This sample courtesy of Sonoma State University Geology Department. [Scale is standard GSA scale with cm divisions.]