Comparative compressibilities of majorite-type garnets

R. M. Hazen, R. T. Downs, P. G. Conrad, L. W. Finger, T. Gasparik

Research output: Contribution to journalArticle

60 Scopus citations

Abstract

Relative compressibilities of five silicate garnets were determined by single-crystal x-ray diffraction on crystals grouped in the same high-pressure mount. The specimens include a natural pyrope [(Mg2.84Fe0.10Ca0,06) Al2Si3O12], and four synthetic specimens with octahedrally-coordinated silicon: majorite [Mg3(MgSi)Si3O12], calcium-bearing majorite [(Ca0.49Mg2.51)(MgSi)Si3012], sodium majorite [(Na1.88Mgp0.12)(Mg0.06Si1.94)Si3O12], and an intermediate composition [(Na0.37Mg2.48)(Mg0.13Al1.07 Si080) Si3O12]. Small differences in the compressibilities of these crystals are revealed because they are subjected simultaneously to the same pressure. Bulk-moduli of the garnets range from 164.8 ± 2.3 GPa for calcium majorite to 191.5 ± 2.5 GPa for sodium majorite, assuming K′=4. Two factors, molar volume and octahedral cation valence, appear to control garnet compression.

Original languageEnglish (US)
Pages (from-to)344-349
Number of pages6
JournalPhysics and Chemistry of Minerals
Volume21
Issue number5
DOIs
StatePublished - Sep 1994
Externally publishedYes

ASJC Scopus subject areas

  • Materials Science(all)
  • Geochemistry and Petrology

Fingerprint Dive into the research topics of 'Comparative compressibilities of majorite-type garnets'. Together they form a unique fingerprint.

  • Cite this