Dissolved in demineralised water, iron (III) nitrate Fe (NO3) 3 gives an orange-brown patina.
Example of a recipe for black / brown patina on bronze;
10 ml iron nitrate, 1 litre demineralised water 2 grams potassium polysulphide (sulphur liver). Prepare the mixture in this order! Apply to the warm bronze with a brush or cloth. Let the object cool down and fix the patina with BICK Bronze Wax
Always use in a ventilated area !!!
Iron (III) nitrate is an iron salt of nitric acid with the chemical formula Fe (NO3) 3. The substance occurs as very hygroscopic light purple crystals that are very soluble in water. The nonahydrate is the most common form and the colour can vary from light purple to ochre-yellow-orange.
For professional use only.