Accession Number: 2017.ch.25
This is a glass disc with a mirrored surface on one face and a clear glass surface on the other. The faces are separated by a rim of heavy glass, approx. 2.5 cm in width. The mirrored surface has three rectangular inlays of a different substance than the main mirror, each of which produces a rainbow in the reflected image. The rim is covered with several layers of fraying masking tape.
Primary Materials: Glass, Fabric Masking Tape.
On the rim of the disc is a yellow sticker, which says “CHEM 387”. There is also a small round pink sticker on the non-mirrored surface, which says “45”.
Diameter: approx. 5.5 cm. Width (thickness): approx. 2.5 cm. The largest rectangular inlay is 4.3 cm x 14.5 cm; the smaller inlays are each 2 cm x 4 cm.
A diffraction grating works like a prism to separate light. It’s part of a spectrometer apparatus, whose function is to both examine the spectra of chemical samples, and determine the effect of specific wavelengths of light on chemical samples.
There are scratches on both faces. Some of the masking tape is fraying, and the glue from the tape has in spots, seeped onto the surface.
Date of Manufacture: Unknown
Acquired from the Dept. of Chemistry, University of Toronto.