Harmunite CaFe2O4: A new mineral from the Jabel Harmun, West Bank, Palestinian Autonomy, Israel

Irina O. Galuskina, Yevgeny Vapnik, Biljana Lazic, Thomas Armbruster, Mikhail Murashko, Evgeny V. Galuskin

Research output: Contribution to journalArticlepeer-review

49 Scopus citations

Abstract

Harmunite, naturally occurring calcium ferrite CaFe2O 4, was discovered in the Hatrurim Complex of pyrometamorphic larnite rocks close to the Jabel Harmun, the Judean Desert, West Bank, Palestinian Autonomy, Israel. The new mineral occurs in larnite pebbles of the pseudo-conglomerate, the cement of which consists of intensely altered larnite-bearing rocks. Srebrodolskite, magnesioferrite, and harmunite are intergrown forming black porous aggregates to the central part of the pebbles. Larnite, fluorellestadite, ye'elimite, fluormayenite, gehlenite, ternesite, and calciolangbeinite are the main associated minerals. Empirical crystal chemical formula of harmunite from type specimen is as follows Ca1.013(Fe 31+957Al0 015Cr3+ 0.011Ti4+0.004 Mg0 0031 993O4. Calculated density is 4.404 g/cm3, microhardness VHN50 is 655 kg/mm2. The Raman spectrum of harmunite is similar to that of the synthetic analog. Harmunite in hand specimen is black and under reflected plane-polarized light is light gray with red internal reflections. Reflectance data for the COM wavelengths vary from ∼22% (400 nm) to ∼18% (700 nm). The crystal structure of harmunite [Pnma; a = 9.2183(3), b = 3.0175(1), c = 10.6934(4) Å; Z = 4, V = 297.45(2) Å3], analogous to the synthetic counterpart, was refined from X-ray single-crystal data to R1 = 0.0262. The structure of CaFe2O4 consist of two symmetrically independent FeO 6 octahedra connected over common edges, forming double rutile-type 1[Fe2O6] chains. Four such double chains are further linked by common oxygen corners creating a tunnel-structure with large trigonal prismatic cavities occupied by Ca along [001]. The strongest diffraction lines are as follows [dhkl, (I)]: 2.6632(100), 2.5244(60), 2.6697(52), 1.8335(40), 2.5225(35), 2.2318(34), 1.8307(27), 1.5098 (19). Crystallization of harmunite takes place in the presence of sulfate melt.

Original languageEnglish
Pages (from-to)965-975
Number of pages11
JournalAmerican Mineralogist
Volume99
Issue number5-6
DOIs
StatePublished - 1 Jan 2014

Keywords

  • Calcium ferrite
  • Harmunite
  • Jabel harmun, palestinian autonomy, israel
  • Raman
  • Structure

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology

Fingerprint

Dive into the research topics of 'Harmunite CaFe2O4: A new mineral from the Jabel Harmun, West Bank, Palestinian Autonomy, Israel'. Together they form a unique fingerprint.

Cite this