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Verification Guide

Assay Verification: Trusting the Numbers on a Certificate

An assay certificate is three claims in one document: that a laboratory performed an analysis, that the sample analyzed came from the goods in question, and that the results are as stated. Each claim fails independently in real fraud cases — forged certificates from real labs, real certificates on switched samples, and labs that exist only as letterheads.

The laboratory

Verify the laboratory exists, is accredited for the analysis performed (ISO/IEC 17025 is the reference standard), and actually issued the certificate in question — most reputable laboratories will confirm certificate authenticity directly when asked with the certificate number.

Sample integrity

The certificate is worthless if the sample is not from the lot you are buying. Sample integrity comes from witnessed sampling with sealed, numbered samples — which is why the assay that matters for a material transaction is the one you commission, with sampling performed or witnessed by an inspection firm answering to you.

Verification checklist

  • Confirm the laboratory's existence and accreditation scope
  • Verify the certificate with the lab by number, through independently sourced contacts
  • Check the certificate ties to the specific sealed samples and lot
  • Commission your own assay for any material commitment
  • Match assay dates to the custody timeline — old numbers do not price today's lot
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