Instructions

To make 250 ml

Make a mark at the 250 ml volume level on your container
Fill container with about 100 ml water
Add acetic acid (99,5% pure) 20 ml (azijnzuur)
Add ammonium chloride 5 g (ammoniumchloride)
Add sodium chloride 5 g (natriumchloride)
Add copper acetate 2 g (koperacetaat)
Add potassium bitartrate 2 g (kaliumwaterstoftartraat oftewel wijnsteen)
Add copper carbonate 5 g (kopercarbonaat)
Solution will now start foaming, leave for 24 hours until settled
Add water to 250 ml

For this project we chose eight different ways to apply the patination solutions to our rings, and each different method of application caused a radically different patina. Other methods of patination are possible, and we encourage you to try different techniques! The ninth piece of every set of rings has not been patinated, this shows the casting skin.

Be aware that everything in the world is made of “chemicals”, and that the tools you use to apply your patination solution can take part in your patination reaction, and change the patina. Use a non-reactive borosilicate glass as a container when working with heat or acids. Avoid using plastics when using heat. For brushing applications, use an inexpensive paintbrush made of natural fibres, such as a hog hair brush.

The specific notes on the application of this patina recipe are in Italic.

Application

A

Applied on the untreated casting skin surface: repeated brush applications of the patination solution on bronze heated with a blow torch. High heat and repeated application will form a dark green crust which rinses off to reveal the milder patina.

B

Applied on a sandblasted surface: repeated brush applications of the patination solution on bronze heated with a blow torch. High heat and repeated application will form a dark green crust which rinses off to reveal the milder patina.

C

Applied on a sandblasted surface: repeated brush applications of two different patina solutions on bronze heated with a blow torch. Application of this patina solution, followed with a silver nitrate patination solution for silver (recipe 7: 5 g of silver nitrate in 250 ml of water). The heat necessary for developing this patina burns the silver patina.

D

Applied on a sandblasted surface: repeated brush applications over the course of ten days on room temperature bronze. Formed an emerald green crust, which rinses off to reveal the milder patina.

E

Applied on a sandblasted surface: boiling of the bronze in a heated patination solution. Darkened the metal.

F

Applied on a sandblasted surface: buried in wood chips soaked in patination solution for a week. Development of a textured patina.

G

Applied on a sandblasted surface: single dip of bronze heated with a blow torch in heated patination solution. Patina does not cover the entire ring and flow lines are visible, multiple dips can even this out.

H

Applied on a sandblasted surface: held in the vapour of a heated patination solution. Resulted in a patchy patina.

I

The untreated casting skin surface: no patination.

Results

Ring 3-A
Ring 3-A magnification 50×
Ring 3-B
Ring 3-B magnification 50×
Ring 3-C
Ring 3-C magnification 50×
Ring 3-D
Ring 3-D magnification 50×
Ring 3-E
Ring 3-E magnification 50×
Ring 3-F
Ring 3-F magnification 50×
Ring 3-G
Ring 3-G magnification 50×
Ring 3-H
Ring 3-H magnification 50×
Ring 3-I
Ring 3-I magnification 50×