Abstract

Abstract Chengdeite occurs in chromite orebodies in dimite as well as in placers in their neighbourhood. The mineral occurs as granular aggregates in association with inaglyite and in some cases occurs as graphic intergrowths with native iridium. It is opaque with a metallic lustre, colour steel‐black, streak black, HM= 5.2, VHN50=452 kg/mm2, cleavage not observed, fracture not observed, strongly magnetic. Its reflection colour is bright white with a yellowish tint. It has no internal reflection, bireflectance or pleochrism, and shows isotropism.Thirteen chemical analyses were carried out by means of the electron microprobe. The mean percentages of the data obtained in the 13 analyses are: s 0.001, Fe 7.9, Ni 0.03, Co 0.03, Cu 0.83, As 0.02, Rh 0.19, Pd 0.00, Os 0.06, Ir 88.5, Pt 2.2 and Pb 0.00. The simplified formula is Ir3Fe, which requires Ir 91.17 and Fe 8.83, the total being 100.00 (%).Five strongest lines of X‐ray powder diffraction (hkl, d, I) are: 111, 2.18 (80);200, 1.89 (60); 220, 1.34 (70); 311, 1.142 (100); 222, 1.094 (80).Through indexing of the X‐ray powder diffraction data, the mineral has been determined to be cubic with Pm 3m, a=0.3792 (5)nm, V=0.05453nm and Z=1.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.