[Ponte Alto] Revisal of ingredients

[Sigrune at aol.com]

Heya Nick,

Now that you explained that you are going to use it for a test on meat, (I am assuming you will be using that old favorite, pig skin) I'll tell you how to go about getting the ingredients.

If you go to home despot you can get lengths of copper pipe, or failing that go for the large pipe fittings. (A good alternative is the outdoor hose spigots, they are usualy cast out of "red brass" which is actualy a form of bronze with a high copper content) With a torch, heat the pipe or fittings up to a dull red heat, let cool (careful where ya put them) and then (when back to room temp) dunk in a strong salt solution remove and let sit, wait a few days until it turns green, scrape off the green gunk and collect it.  The heat will get the process of oxidation going nicely, and burn off any surface contaminants and corrosion protection, as well as opening the surface pores to speed the reaction with the oxygen. (FYI if you dunk the piece in the salt solution while hot, you will be annealing the copper, this makes it soft and arranges the copper molicules into a pattern that is not as condusive to corroding as if you let it cool slowly)

I don't know where you can get iron sulfate, but black iron oxide should substitue well, it is a common agent used to darken pigments throughout history.  Get a cheap metal chisle (the thinner the better) from the tool corral at HD, and once again subject to fire, what you want to do is actualy get it up to a bright yellow heat when it starts to spark. What is happening is the carbon has been heated to such an extent that it is fleeing from the iron matrix of the steel, this will leave a pitted and blistered chunk of metal. Let it cool and scrape off the deteriorated steel, grind it fine in a mortar and pestle and Viola, iron oxide.  (Speaking of which I am going to have to make some more myself, it is one of the ingredients used in polishing japanese swords.)

As a substitute for the gall and the egyptian pine bark, I would go with crushed and powdered walnut hulls. Another alternative is the brown fibers from coconut husk.

Just a few ideas,

Takeda