Hello I posted a similar question before, Yet I am trying to learn how to identify a piece of rough that may produce asterism. I have some material of rough ruby and sapphire, it was a bulk amazon cheep buy I was just hoping it would contain some material however small that was facet grade. It does not but there are a few pieces that may make a decent Color cab. Is there a way to look at a piece of rough to determine if it may yield a star sapphire? This material has a strong laminar cleavage I found after tumbling.
To bring out asterism how should I orientate the stone in relation to the cleavage? And is it a hit and miss excersise.
Thank you Kindly