Thanks. It is easy to find quartz, which is harder than glass, so scratch quartz and it gives even better hardness identification for things like spinelLoneWolf said:If you have a read through goldierocks excellent thread titled ' Series on identifying Minerals' it may be of some help.... An SG test will be one of the best tests you can do besides a 'scratch' test which you have already done (scratches Glass) .... Both of these methods will determine in most cases what it is...
LW....