This sample of eosphorite is displayed in the Smithsonian Museum of Natural History. Eosphorite is a phosphate mineral with the composition (Mn,Fe)AlPO4(OH)2.2H2O. The sample at left is about 30 cm across and is from Black Mountain, Rumford, Maine.
The sample of eosphorite at right is from Conselheiro Pena, Minas Gerais, Brazil. It is about 5x12 cm.
The brown crystalline cluster of eosphorite at left is about 3 cm across.