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A new miniphotometer for teaching and routine work in ore microscopy

Published online by Cambridge University Press:  05 July 2018

M. Tarkian ,
E. F. Stumpfl  and
H. Matthies
M. Tarkian
Affiliation:
Mineralogisch-Petrographisches Institut, Universität Hamburg
E. F. Stumpfl
Affiliation:
Mineralogisch-Petrographisches Institut, Universität Hamburg
H. Matthies
Affiliation:
Mineralogisch-Petrographisches Institut, Universität Hamburg
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Summary

A simple and easy-to-use miniphotometer has been designed; the expense involved amounts to only a fraction of that required for large commercially available microphotometers.

The instrument can be employed for routine investigations and for teaching reflected light microscopy in conjunction with standard reflected light microscopes.

The reflectance of grains down to 50 μm size can be measured in white and monochromatic light employing continuous band and line interference filters. The systematic error does not exceed 1.5 % of the values measured. The only aspect that distinguishes the miniphotometer from larger instruments is the limitation of spot size. A comprehensive test programme including comparative sets of measurements on a Zeiss MPM spectral microphotometer has shown that the results obtained by both instruments coincide well.

Type
Research Article
Information
Mineralogical Magazine , Volume 40 , Issue 309 , March 1975 , pp. 97 - 103
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1975

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Footnotes

1

Present address: Montanistische Hochschule, Leoben, Austria.

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