The most effective colloidal silver preparation is produced by American Biotech Labs . I know about it as I have a few Clifton Mining shares, a small US explorer which has an interest in one particular patented process. Jason Hommel also refers to it in his exhaustive listing of world junior silver explorer & producers. Apparently it has permission from the govt of Ghana for use against malaria. However, I have not found the silver colloidal preparations that you buy in Sydney shops any use.Although I am not speaking ill of retailers with a great herbl tradition like Nelsons .Perhaps the particle size is wrong,the bottle has sat on the shelves too long or the light has damaged it. I would like to hear from anyone who has actually tried colloidal gold- either on a do it yourself basis or from a store purchase- if that is possible.