Artificial glass showing color change when exposed to light.

This article explores the characteristics of artificial glass. It identifies the properties that were obtained through standard gemological testing: hydrostatic, polariscope reaction, and ultraviolet (UV) fluorescence. It notes that no radioactivity was detected with a Geiger counter and microscopic examination revealed no inclusions. It notes that the spectrum of the light yellow state showed only a very slight increase in absorption toward the blue region and that the spectrum of the dark bluish gray state revealed a broad absorption.