Will,
The basic difference is charcoal blues primary ingredient is bone charcoal and is usually done like case color, in a box, but at less than 1000f, Carbonia blues primary ingredient is oil and it is done in a furnace, in an atmosphere created by the semicombusted charge. Carbonia is more durable than charcoal blue in my experience, or any other of the prewar blues.
I have been using the same batch of brownells nitre salts for 20 years, and they work great. I am sure there are many ways to skin the cat when it comes to recipes.
Last edited by Barry Lee Hands; 07/21/08 11:36 AM.