Abstract:
In this paper a detailed study is made of the absorption of light in the visible region by amethyst quartz. It is found that in the visible region, an absorption band, the so called F-band appears, which decreases in intensity at high temperature the maximum also shifts ton~ardslo nger u~arelengths; but the number of colour cenires remain constant till about zoirEC. At higher fen~peratures these centres, which are responsible for the absorption, are destroyed by heat. When the crystal is exposed to radiation absorbed by the F band, a new F'-band appears. The facts reveal that the coloration is due fo exposure to some penetrating radiations.
