True test, 7. Wish you were here. Good read:
Post# of 5949
California NORML and Project CBD release the results of the first “Ring Test” to assess the accuracy of analytical laboratories
Mixed findings show strengths and problems among analytic testing services.
http://canorml.org/news/ringtest.html
http://www.canorml.org/RingTestOShaughnessys_Aut11.pdf