A relation between the density and refractive index of silicate glasses, with application to the determination of imitation gem-stones

F. A. Bannister
1929 Mineralogical Magazine and Journal of the Mineralogical Society  
It has long been possible to identify readily many minerals by means of density and refractive index determinations, and the chemical composition also can often be approximately deduced. Tilley has shown that it is practicable to determine any natural glass by this method and be succeeded in separating the natural glasses into groups characterized by certain limits of specific refractivity. As far as the author is aware, no such systematic method has been described for distinguishing the
more » ... guishing the artificial glasses one from the other, and it is these glasses that we are concerned with in attempting to determine the approximate composition of an imitation gem-stone without the aid of chemical analysis.
doi:10.1180/minmag.1929.022.126.02 fatcat:vrt3l5fmy5bfljiedplcqtwedy