Here is a link to the Micromark page for Blacken-It
I've ordered lots of things from Micromark.
Here is are step by step instructions for using Blacken-It on an army model.
I bought Patina-It this weekend... I'm not really happy with how it looks. It looks more like I painted the metal green rather than actually turning the metal green. It also rubs off easily.
This is a different brand but it came up every time I did a search for aging metals.
If At First You Don't Succeed...
9 hours ago