Borax bead test
A chemical test to disclose the presence of certain metals in a sample. A clear
glassy bead of borax fused in a wire loop will react chemically with the salts
of certain metals and yield colors that help to identify the metal; e.g.,
manganese compounds produce a violet bead, cobalt produces a deep blue, etc.
See also: blowpiping
Source: Dictionary of Mining, Mineral, and Related Terms