These kits offer ease of use and sensitivity for the amplification of immunogold labels in electron and light microscopy and blotting applications. Enhancement occurs during the reduction of silver from one solution (the enhancer) by another (the initiator) in the presence of gold particles. This reduction causes silver to build up on the surface of gold particles, with no diffusion of the signal due to the discrete nature of the silver growth on the gold particles. Enhancement is rapid and easily controllable; the reaction can be monitored in bright light and terminated by washing in tap water, with signal amplifications of x10 - 100 readily achieved. Two silver enhancing kits are available for different applications, an EM/LM kit and a blotting kit.