Shandite from the Itoigawa district, Niigata Prefecture, central Japan.

Accession number;99A0290912
Title;Shandite from the Itoigawa district, Niigata Prefecture, central Japan.
Author;MIYAJIMA H(Fossa Magna Museum, Niigata, Jpn)   MATSUBARA S(National Sci. Museum, Tokyo, Jpn)   MIYAWAKI R(National Sci. Museum, Tokyo, Jpn)   HAYASHI T(Fossa Magna Museum, Niigata, Jpn)   
Journal Title;Journal of Mineralogy, Petrology and Economic Geology
Journal Code:F0509A
ISSN:0914-9783
VOL.93;NO.11;PAGE.427-436(1998)
Figure&Table&Reference;FIG.6, TBL.3, REF.18
Pub. Country;Japan
Language;English
Abstract;The rare and unique nickel lead sulfide mineral, shandite, Pb2Ni3S2 has been found as a minute aggregate in the kosmochlor-bearing eckermannite rock from the Itoigawa district, Niigata Prefecture, central Japan. It occurs in association with galena, undetermined nickel arsenide and heazlewoodite. The occurrence of shandite is different from the other parageneses previously reported. Electron microprobe analyses of shandite indicate no compositional variations among individual grains and lead to the empirical formula, Pb1.96Ni3.02S2. The X-ray diffraction pattern obtained by a Gandorfi camera is indexed on the trigonal cell with a=5.594(2) and c=13.599(4).ANGS.. The shandite is interpreted to have formed by cotecitc crystallization with galena and heazlewoodite in the ultramafic rocks. It is thought to be a relict mineral derived from the ultramafic rock. (author abst.)
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