What element is primarily used in the Fuming Gun Method for fingerprinting?

The Fuming Gun Method, which is employed for developing latent fingerprints, primarily utilizes iodine as its active element. When iodine is heated, it sublimates to form vapors that interact with the fatty acids and oils present in the fingerprint residues on surfaces. This reaction results in the visualization of the fingerprints, producing a brownish stain that can be photographed or otherwise documented.

Iodine is a suitable choice for this method because it is a non-destructive technique that can be used on a variety of surfaces without damaging them. It allows for the temporary visualization of fingerprints, as the iodine will gradually fade, necessitating documentation of the prints quickly.

Other methods mentioned, such as ninhydrin, carbon, and Freon 113, serve different roles in latent fingerprint development. Ninhydrin is commonly used for processing fingerprints on porous surfaces, while carbon is not typically associated with a fuming method. Freon 113, an older solvent, would not be utilized in this context due to safety and environmental concerns.