A product of contact metamorphism of siliceous limestones and dolostones, and in rocks of the sanidinite facies. Also, forms from alkalic magmas rich in calcium.
Valid Species (Pre-IMA) 1884
Occurrences are typically of intermediate series members; relatively pure examples have been found at Monte Somma and Vesuvius, Campania, and Monte Cavalluchio, Sacrofano, near Rome, L
Link to MinDat.org Location Data.
For Anders Richard Akerman (1837-1922), Swedish metallurgist.