Research on the genesis of rare metal deposits by SIMS analyses

2014 Fiscal Year Final Research Report

• Project/Area Number: 23540565
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Petrology/Mineralogy/Science of ore deposit
• Research Institution: Shizuoka University (2013-2014); National Institute of Advanced Industrial Science and Technology (2011-2012)
• Principal Investigator: MORISHITA Yuichi 静岡大学, 理学(系)研究科(研究院), 教授 (90358185)
• Co-Investigator(Kenkyū-buntansha): HIYAGON Hajime 東京大学, 大学院理学系研究科, 准教授 (70192292)
• Research Collaborator: HAMMOND Napoleon Q. Department of Geology, University of Limpopo Turfloop Campus, South Africa, School of Physical and Mineral Sciences, Senior Lecturer-Economic Geology
• Project Period (FY): 2011-04-28 – 2015-03-31
• Keywords: SIMS / レアメタル / 南アフリカ共和国 / 白金族鉱床 / 金鉱床

Outline of Final Research Achievements

Analytical techniques for Pt and Pd in sulfide minerals by secondary ion mass spectrometry were examined to obtain precise measurement conditions using ion-implanted standard mineral samples. Calibration of Pt or Pd concentration was conducted using external standard samples of pyrrhotite, pentlandite or chalcopyrite implanted with Pt or Pd ions at 1.3 or 0.8MeV, respectively. After analyzing a standard for depth profiling, the depth of the sputtered borehole was measured using a surface profiler to determine the relative sensitivity factor (RSF).
SIMS microanalysis for Merensky Reef pentlandite grains gave high Pt (more than 10ppm) and Pd (several hundred ppm) concentrations. Pt or Pd concentrations were very low and fluctuating in pyrrhotite or chalcopyrite grains. Although Au concentration was 0.1ppm on average, it was fluctuating. Pt and Au concentrations are not spatially correlated in a micro area, suggestion different formation mechanisms for Pt and Au.

Free Research Field

鉱床学