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Quantity of chemical to use for 16'x3' copper (Hughes book question)

2006

I've just bought the Hughes book-- "The Colouring, Bronzing & Patination of Metals" [on eBay, Amazon, AbeBooks affil links] ...and I can't find anything describing the quantity of chemical I need for surface area. I've got 16'x3' of copper to patina and need to know what it will take to cover it all before I place my order. Anyone familiar with these recipes and how much surface they can cover? if not here is the recipe for one patina I'm doing, but it doesn't mention how much it will cover...it is soaked into cotton balls which cover the sheet so I assume the litre will be quickly soaked up:

ammonium carbonate 150 gm
copper acetate [affil links] 60 gm
sodium chloride 50 gm
potassium hydrogen tartrate 50 gm
water 1 litre

thanks for your help,

Jenny De L'Isle

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2006

I studied Hughes book today at the library and found what I needed to do...now I need to find the chemicals

ammonium carbonate (150gm): is this the same as baker's ammonia..I've seen an ounce of baker's ammonia ⇦ this on eBay or Amazon [affil links] for 3 dollars and then I found 500ml from a chem. dealer for 26.

copper acetate [affil links] & copper nitrate ⇦ this on eBay or Amazon [affil links] (60 gm): haven't found anywhere?

potassium hydrogen tartrate or cream of tartar (50gm): is food grade good for my purposes?

also calls for sodium chloride and I can find that.

any ideas on where to find these? also I have to patina 3 x 16 feet of copper. I forgot to look in the book to see how much the prescribed doses cover..any idea on how much to use to cover that much copper?
thanks a lot,

Antonin De L'Isle

Try any good chemist shop. Simpler recipes for green patina exists too, even in Hughes/Rowe book...Food grade chemicals must be usable(kitchen salt and cream of tartar). Hope it helps and good luck!

Goran Budija

2006