E. J. Gübelin, September 1, 1982
This article reports on three gem materials currently being mined in Pakistan.
Read MoreRobert E. Kane, December 1, 1984
An examination and analysis of 15 natural rubies with glass-filled cavities.
Read MoreSam Mulhmeister, Emmanuel Fritsch, June 1, 1998
Natural and synthetic gem rubies can be separated on the basis of their trace-element chemistry.
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