The bead is dipped into a tiny amount of the compound to be tested and is reheated in the flame. The metal borate that is formed colors the bead. If too much of the unknown compound is used, the bead may be opaque and the color difficult to determine. A different color is often obtained in a reducing flame. Several metals may give the same color.
Some metals give only colorless or gray beads.
A test similar to the borax bead test is often made using microcosmic salt. Results of the bead test may be confirmed by other methods of chemical analysis .