1991 Volume 40 Issue 6 Pages 219-225
A new observation method of colored luminescence or after-glow (phosphorescence), emitted from rock slices immediately after γ-ray irradiation, has been developed using a normal color-film. The film was directly faced to the irradiated slices for a relatively short period like 2-5 min in a black bag. According to this simple procedure, the resultant photographs showed unexpectedly colorful images depending on the mineral constituents in slices. The intensities of the after-glow color images (referred to as AGCI) were found to be dependent on the dose rates rather than total doses. In the AGCI, the apparent variations of emission intensity were observed even within individual minerals as well as color changes affected by thermal metamorphism. A qualitative decay behavior has been clearly seen in the successive AGCI results. The proposed conventional AGCI technique is considered to become a promising tool applicable to varieties of mineralogical investigations as well as the additional information concerning the intrinsic physical properties of other solid materials.