Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Origin of platinum-group mineral assemblages from placers in rivers draining from the ural-alaskan-type Itchayvayamsky ultramafics, Far East Russia

Eugene G. Sidorov, Anton V. Kutyrev, Elena S. Zhitova, Valery M. Chubarov and Dmitry A. Khanin
Origin of platinum-group mineral assemblages from placers in rivers draining from the ural-alaskan-type Itchayvayamsky ultramafics, Far East Russia
The Canadian Mineralogist (January 2019) 57 (1): 91-104

Abstract

The Itchayvayamsky Ural-Alaskan-type massif is located in the northernmost part of the Koryak-Kamchatka Platinum Belt (Russia) and is surrounded by two rivers (Kamenistaya and Itchayvayam) that both contain specific PGM (platinum group minerals) assemblages. The PGMs of the Kamenistaya River are represented by isoferroplatinum with minor admixtures of Pd and Cu (up to 1.97 and 1.37 wt.%, respectively) and numerous inclusions of other PGMs such as laurite, erlichmanite, and boweite. The Itchayvayam River assemblage is different, as it contains minor amounts of isoferroplatinum and other minerals identical to those of the Kamenistaya River, as well as abundant native platinum rich in Cu and Pd (up to 4.30 and 2.34 wt.%, respectively) and rimmed by secondary cooperite and malanite. Grains of gold intergrown with unnamed Au-Hg-Pd minerals, cooperite, vysotskite, and malanite were also found exclusively in the Itchayvayam River. Three mineral assemblages are spatially related to the Itchayvayam massif and are distinguished by: (1) isoferroplatinum, (2) native platinum, and (3) gold-mercury-palladium. Isoferroplatinum assemblages are typical for placers derived from Ural-Alaskan-type massifs and lodes (e.g., the Galmoenan massif in the Koryak Highlands). Simultaneously, the native platinum assemblages are rare and have been described as lodes in clinopyroxenites, and in sub-economic placers derived from clinopyroxenite-dominant massifs. Therefore, it is assumed that the origin of the first assemblage is from lodes in dunite and the second is from lodes in clinopyroxenite. In addition, gold-mercury-palladium assemblages apparently originated from mineralized zones, analogous to those intruding gabbro and monzonite at the nearby Barany massif, which contains native gold and Pd-sulfides. Our study of the structure and compositions of Pt-Fe minerals showed that in the structure of isoferroplatinum Cu and Ni substitute for Fe, whereas in native platinum they substitute for both Pt and Fe.


ISSN: 0008-4476
EISSN: 1499-1276
Coden: CAMIA6
Serial Title: The Canadian Mineralogist
Serial Volume: 57
Serial Issue: 1
Title: Origin of platinum-group mineral assemblages from placers in rivers draining from the ural-alaskan-type Itchayvayamsky ultramafics, Far East Russia
Affiliation: Russian Academy of Sciences, Institute of Volcanology and Seismology, Petropavlovsk-Kamchatskiy, Russian Federation
Pages: 91-104
Published: 20190130
Text Language: English
Publisher: Mineralogical Association of Canada, Ottawa, ON, Canada
Number of pages: 14
References: 44
Accession Number: 2019-016973
Categories: Mineralogy of non-silicatesEconomic geology, geology of ore deposits
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 4 tables, sketch map
N58°00'00" - N63°00'00", E161°00'00" - E172°00'00"
Secondary Affiliation: St. Petersburg State University, RUS, Russian FederationLomonosov Moscow State University, RUS, Russian Federation
Country of Publication: Canada
Secondary Affiliation: GeoRef, Copyright 2019, American Geosciences Institute. Abstract, copyright, Mineralogical Association of Canada. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201911
Close Modal

or Create an Account

Close Modal
Close Modal