The Sodium Rhodizonate test provides a color reaction indicative of the presence of lead. It can be employed around the periphery of a hole or defect to determine if it is consistent with the passage of a bullet. Lead may be deposited not only from lead bullets, but from lead residues found on the exterior of most fired copper-jacketed bullets as well. At the scientist’s discretion, the test may also be used to evaluate other objects or surfaces for the presence of lead.
The hole (above left) is to be tested with sodium rhodizonate solution. The control test (above right) shows the reagent is giving expected results, a purple color reaction to the area to which lead was applied. The bullet hole is tested by transferring lead to a filter paper with an acidic solution on it (below left) and then applying sodium rhodizonate solution to obtain the color reaction (below right). This reaction is indicative of bullet wipe and shows the hole is consistent with the passage of a bullet.