The conclusion is in showing just how valuable of an asset these specific tests really are towards the outcome of numerous investigations from the past and in the present.
The materials that are found to make up gun powder residue and seemingly found to predominantly consist of a mixture including organic and non-organic substances are basically elemental metals, among other items. However, it has been determined by a number of forensic analysists that only the materials involving primarily metallic residues are the most applicable to be used in testing procedures (RML 2004). There are also specific types of metals found in the residue left behind by a gunshot that are more detrimental than others. These metals are found to be highly sensitive to forensic tests and consist of: lead, antimony, barium, and sometimes copper is another one of the metals that is attempted to be obtained as well. The reason for analyzing gunpowder residue and the various other elements traceable in it proves highly beneficial in investigations where a determination of homicide or self defense is in question. The most commonly used tests that are carried out on these metallic materials are atomic absorption or AA and also microscopy with energy dispersive X-ray analysis or otherwise popularly known as the renowned SEM/EDX test (RML 2004).
Past experiences within the extensive testing areas have shown that the secondary method proves to be the most reliable and conclusive in validating pertinent data to prove a case. However, the negative of choosing one over the other is the fact that once one of these methodologies have been chosen and implemented, the other test would be useless to incorporate as well due to the evidence already having been affected by the previous test. This can pose problems, especially if the chosen test does not prove to find any reliable data or present with results that would help the case. Basically, the whole process would have to start again with trying to gather more field data from the crime scene and hopefully finding enough residues to utilize a new test and come up with better results. However, the SEM/EDX has always proven very worthy for investigators although it is the more expensive test and takes up a considerable amount of time to return the most accurate results. Using any one of these methods, there is often a reasonable determination reached in regards to the pattern of the gun powder residue left on the target and evaluating how close the muzzle of the weapon