Recipe 4

To make 250 ml

Make a mark at the 250 ml volume level on your container

Fill container with about 100 ml water

Add sodium thiosulphate 60 g (natriumthiosulfaat)

Add copper acetate 10 g (koperacetaat)

Add citric acid 10 g (citroenzuur)

Add water to 250 ml

Let solution age for four days before applying.

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.

A

Applied on the untreated casting skin surface: repeated brush applications of the patination solution on bronze heated with a blow torch. This patina requires high heat and repeated application. Heat very gently, as local heat differences will give different coloured patinas. This patina can easily be burned to make the colours less vibrant.

B

Applied on a sandblasted surface: repeated brush applications of the patination solution on bronze heated with a blow torch. Heat very gently, as local heat differences will give different coloured patinas. This patina can easily be burned to make the colours less vibrant. The lighter tone of the sandblasted surface shows the colours better.

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). This dulled both patinas.

D

Applied on a sandblasted surface: repeated brush applications over the course of ten days on room temperature bronze. Resulted in a patina of metallic colours.

E

Applied on a sandblasted surface: boiling of the bronze in a heated patination solution. Went through the range of orange, blue and violet to black.

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. Results in a very even patina.

H

Applied on a sandblasted surface: held in the vapour of a heated patination solution. The full range of colours occurs before culminating in the black.