Testing Methods for Precious Metals

Because we want to give our customers the fairest valuation for their lots, MGS specializes in several types of assays, or testing methods. Depending on the amount of precious metals and the form they’re in, some assays can be more efficient than others. This chart quickly shows the key differences between the assays we offer. Click on an assay to learn more about how it works.

  Acid Testing X-RF-Analysis Fire Assay Ultrasonic Testing
Accuracy 10-20 parts per thousand 2-5 parts per thousand 1-5 parts per ten-thousand 100%
Destructive? No Yes Yes No
Time for Results Instant two minutes 1-2 days Instant
Cost Free $5 $25 Free
Useful for testing... most small lots filing dust, polishing material and non-plated metals very large lots of mixed materials bullion authenticity