Test a metal's purity (5)
I believe the answer is:
assay
(Other definitions for assay that I've seen before include "Analyse to find the properties" , "Evaluate" , "Test quality of metals" , "metallurgical test" , "Put to the proof" .)
I believe the answer is:
assay
(Other definitions for assay that I've seen before include "Analyse to find the properties" , "Evaluate" , "Test quality of metals" , "metallurgical test" , "Put to the proof" .)