Microscope Accessory Plates and Colour Blindness

F. E. Tocher
Department of Geology and Mineralogy, University of Aberdeen

Summary: The ordinary quartz wedge is adapted for use by the colour blind by the superposition of a two-colour isotropic auxiliary plate. A birefringent plate of suitable retardation may also be used in conjunction with the same auxiliary plate to replace the standard sensitive tint plate. In both cases, diagnostic colour changes are replaced by relative intensity changes.

Mineralogical Magazine; September 1964 v. 33; no. 266; p. 1002-1007; DOI: 10.1180/minmag.1964.033.266.07
© 1964, The Mineralogical Society
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