gems, laboratory procedures, origin determination, country of origin

The proliferation of gemmological laboratory reports and the increasing emphasis on transparency to mitigate legal risk suggest that some gem-testing laboratories should revise the wording and content of their geographical origin reports. Drawing on the author’s broader study of legal issues surrounding expert opinions in the fields of art and antiques, the key proposals are: that opinions, rather than facts, be clearly identified as such within the main body of the report—not solely in the ‘terms and conditions’; that the observational or analytical basis for these opinions be briefly stated; and that laboratories consider indicating the level of confidence associated with their conclusions.