Sunday 14 February 2021

Meddling with madder - part 2

 The results of the dilution test after 24 hours in the madder solution.

With the first experiment on colouring antler with madder done, the basic recipe was elucidated. The next step was to determine which strength of solution led to which red colour strength. To do this a set dilutions was made. So, to recapitulate, the basic recipe was:

  • Pre-soaking antler for 1 hour in water
  • Make madder solution with 4 gram sodium in 400 ml water (a 1% solution) + 5% WOF madder extract for 1 hour at 60 degrees Celsius
  • Antler for 2 hours in madder solution at 60 degrees Celsius
  • Cool down for 24 hours in madder solution
  • Rinse with cold water

Dilution test

For the dilution test a set of five different solutions was made. The basic madder solution was diluted with a 60 degrees Celcius 1% sodium solution in 5 different glass jars:

  • 100%  = 200 ml basic madder solution
  • 50%  = 100 ml basic madder solution + 100 ml sodium solution
  • 30%  = 60 ml basic madder solution + 140 ml sodium solution
  • 20%  = 40 ml basic madder solution + 160 ml sodium solution
  • 10%  = 20 ml basic madder solution + 180 ml sodium solution

The results of the dilution test directly after 2 hours at 60 degrees C. The (quarter) antler pieces are at the back, while the elongated bone pieces are at the front.

As I also had some (cow) bone pieces leftover from making soup, these were added as well to the test. The antler and bone responded differently to the dilution test. The bone produced a much lighter shade of red than the antler. This could be due to the fact that the bone was still 'fatty', and thus less able to absorb the madder. Or it might be that (cow) bone is less able to absorb the madder than antler. The 50% solution looked most agreeable to me, having a full red colour and not being too dark red. This solution was chosen for the production of the coloured tablemen.

Finalisation

The results of the actual colouring of the tablemen were not as straightforward as thought. The coloured antler game pieces had different shades of red, giving it a spotted appearance. Also, a wet solution brings out the fibres (just like wood), giving the game piece a slightly rough texture. Especially, the porous inside of the antler produces the most 'rough' texture and needs sanding to make it smooth again. The first game piece was sanded to much, and blank bits appeared. Therefore, I repeated the colouring procedure on the same game pieces in order to darken and recolour the light coloured spots. The result was that the game pieces were now a dark red colour.

 
 When you saw the test pieces in half you can see that the madder colour consists only of a small layer on the bone and antler. only on the porous part it invades further into the tissue.
 
 
The wet tablemen showing a spotty colouring.

When the tablemen were dry, the porous parts were carefully sanded with a 320 grid sanding paper, after which the complete gaming piece was polished with a cotton polishing wheel. Afterwards the piece was oiled with walnut oil, just as it was described in the 12th century treatise by Theophilus. 

 
The 100% and 50% madder solution test pieces with walnut oil.
 
 
Some of the madder coloured and uncoloured antler tablemen after the walnut oil finish.