Occurs in Pinal County.
Chemical Formula: (Na,Ca)0.3Al2(Si,Al)4O10(OH)2·nH2O
Specific Gravity: 2.6-2.8
Hardness: 1-2 Beidellite is a member of the smectite group of clay minerals. It has a high water content and is often found in soils and sedimentary environments.