The Structure of Junitoite, CaZn2Si2O7·H2O

R. D. Hamilton and J. J. Finney
Department of Geology, Colorado School of Mines, Golden, Colorado 80401, USA

Abstract: Junitoite, CaZn2Si2O7·H2O, is orthorhombic, space group Area2, with a = 12.510, b = 6.318, c = 8.561 Å, Z = 4. The structure, determined on the basis of three-dimensional Mo- intensity data for 745 reflections refined to R = 0.10. The structure consists of ZnO4 tetrahedral chains along b joined by Si2O4 groups along a and c to form a three-dimensional network. Ca occurs in distorted CaO5(H2O) octahedra. The structure shows similarities to hemimorphite and Ca-Zn silicates but represents a unique tetrahedral framework.

Keywords: crystal structure • junitoite

Mineralogical Magazine; March 1985 v. 49; no. 350; p. 91-95; DOI: 10.1180/minmag.1985.049.350.13
© 1985, The Mineralogical Society
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