There are a lot of tutorials on the net on how to make colloidal silver. Many of them basically go like this - Hook up two 99.99% silver coins or wires to three 9V batteries, and put the silver in saline, an inch apart, for a few minutes. Does this make real colloidal silver or silver ionic silver or silver chloride?
Here's an example: http://www.instructables.com/id/How-to-make-COLLOIDAL-SILVER-Easy/