Is a rare mineral found only in Sterling Hill locality.
The formula is Mg15(SO4)2(OH)26·8H2O and hardness of 3.
Associated with Pyrochroite, a manganese hydroxide with formula Mn(OH)2 and hardness of 3.
As a must from this location there is Willemite that gives it's green fluorescence. From Sterling Hill Mine,Ogdensburg,New Jersey.