Duluth Complex Magnetite Fractionfiles.dnr.state.mn.us/lands_minerals/mpes_projects/mpes_389...Duluth Complex Magnetite Fraction Electron Microprobe Analyses Peter McSwiggen ... Symplectite:

Duluth Complex Magnetite Fraction

Electron Microprobe Analyses

Peter McSwiggen McSwiggen & Associates

Electron Microprobe Analyses June 30, 2013

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Sample: 003

McSwiggen & Associates

Sample Overview

3

Sample: 003


Sample Overview

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Sample: 003


Oxide Chemistry

5

Sample: 009


Sample Overview

6

Sample: 009


Sample Overview

7

Sample: 009


Oxide Chemistry

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Sample: 011


Sample Overview

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Sample: 011


Sample Overview

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Sample: 011


Oxide Chemistry

11

Sample: 026


Sample Overview

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Sample: 026


Sample Overview

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Sample: 026


Oxide Chemistry

14

Sample: 039


Sample Overview

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Sample: 039


Sample Overview

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Sample: 039


Oxide Chemistry

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Sample: 066


Sample Overview

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Sample: 066


Sample Overview

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Sample: 066


Oxide Chemistry

20

Sample: 088


Sample Overview

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Sample: 088


Sample Overview

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Sample: 088


Oxide Chemistry

23

Sample: 092


Sample Overview

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Sample: 092


Sample Overview

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Sample: 092


Oxide Chemistry

26

Sample: 099


Sample Overview

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Sample: 099


Sample Overview

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Sample: 099


Oxide Chemistry

29

Sample: 103


Sample Overview

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Sample: 103


Sample Overview

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Sample: 103


Oxide Chemistry

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Internal Textures


Symplectite: titanomagnetite in olivine Sample 026

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Internal Textures


Weathered exsolution magnetite/ilmenite Sample 066

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Internal Textures



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Internal Textures



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Internal Textures


Sample 066 Fe oxide ovoid

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Internal Textures


Sample 066 Rutile rim on titanomagnetite

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Internal Textures


Weathering: Fe oxide-hydroxide surrounding magnetite

Sample 066

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Internal Textures


Symplectite: titanomagnetite in olivine Sample 092

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Internal Textures


Weathering rinds Sample 092

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Notes


Backscattered electron imaging of the samples showed that the grains were extremely complicated with both intergrown minerals and later weathering. It was determined that rim versus core analyses would not provide any useful information. No primary mineral zoning was observed in the backscattered electron images. Each sample was extensively search for PGM grains. None were found.

Documents

Duluth Complex Magnetite Fractionfiles.dnr.state.mn.us/lands_minerals/mpes_projects/mpes_389...Duluth Complex Magnetite Fraction Electron Microprobe Analyses Peter McSwiggen ... Symplectite: