The coke purity testing kits I'm aware of might be found at the same places you buy your EZ testers from. The purity testers are available over the web but I can't imagine that they would go through customs unnoticed and the sites that sell them also stock other things and as such I won't be listing them on this board. I have no idea if these kits actually work either I've heard about them but never seen them in action.
[ 13 September 2002: Message edited by: Fry-d- ]