Stilbite Subgroup, Lévyne-Ca, Offretite, Smectite Group
SE Lava Drive, Milwaukie, Clackamas County, Oregon, USA
Crystals rectangular, elongated, of " 'stilbite subgroup'", colorless, shiny, aggregates as to make toothed wheels, intertwined with each other to form as spheres, with the terminations of distinct crystals. On the top, hexagonal, thin, white crystals of lévyne-Ca, on which acicular, darker, offretite crystals grew on rich iron smectite. ...