Boggsite, a new high-silica zeolite from Goble, Columbia County, Oregon

Abstract

The new zeolite boggsite occurs as small, colorless-to-white, zoned hemispheres embedded in drusy tschernichite in small vesicles in dense Eocene basalt near Goble, Columbia County, Oregon, where it formed through the action of local hydrothermal activity. The mineral is orthorhombic, space gtoup Imma, with 4 : 20.21(2), b : 23.77(l), and c : 12.80(l)A.ttrestrongestX-raydiffractionlinesare(inA) tt.f(tOO),4.43(70),3.86(80), 3.37(100). The chemical composition is near (CarrNar.rKorMgo')(Feo,Al,83sii76)Ore2' 70H,O, with Z : l, Si/Al : 4.24.Ir is optically biaxial (-), with a : 1.480(l), 0 : 1 .481 ( l ) , and7 :1 .487 ( l ) ,whe reX :c ,Y :a ,Z :b .Thedens i t y i s1 .98 ( l ) g / cm3(obs ) , 1.99 g/cm3 (calc). Tiny blades of boggsite with the forms {01l}, {102}, {010}, {100}, and {001} elongated along the b axis have a morphology similar to that of thomsonite. The name honors Robert M. Boggs of Seattle, Washington, and Russell C. Boggs of Cheney, Washington.