Monday, March 6, 2017

W h i t e s h e l l / Colour of the Month #4

In March we're celebrating Whiteshell colour made from disposed eggshells! It's fascinating to know that eggshells were used for multiple purposes in Antiquity.  In Egypt, ostriches were quite used animals; the feathers for decoration, the eggs for food and the shells for ornamentation and pigment. I can say that holding an ostrich eggshell is a fascinating experience; admiring its colour, size, texture and hardness makes you think about the beauty in nature.

From eggshells

Etymology: ovum
Source: animal
Composition: calcium carbonate
Colour range: white, beige, pale pink

Some history...

The size of an ostrich egg can be up to fifteen centimetres in length and thirteen centimetres in diameter with a shell thickness of up to 3,5 millimetres and can weight up to 1,5 kilograms.

The eggs were used as an ingredient for medicine because its composition is basically calcium. The consumption of ostrich meat was evident as well as the use of egg ‘glaire’ (white) as a binding medium for paint. The eggs were decorated and the vessels were made from the shells, which were embellished with precious metals and other ceramic pieces.

These were used as containers for various purposes to keep precious things and for perfume. The egg would be drained, then cleaned and decorated before it was used. Eggshell jewelry was common; shells were worked into jewelry beads possibly for ear, forehead or clothing ornaments with amulet purposes.

During the Middle Ages, whites made from eggshells and calcinated bird bones were quite common used for painting. Medieval painters mostly used minerals and recycled organic materials for making pigments, sourced locally or imported. The main colours were blues, reds, greens, blacks, yellows and whites from lead and eggshells.

Collecting eggshells at home can become a playful and sustainable hobby, all of this to make white pigment. My kitchen is full of containers filled with eggshells. Almost every day I eat fresh free range boiled eggs. After peeling the egg, I just wash the shells and let them dry for 2 days and they will be ready for grinding them up.

It is fantastic to see all the colour ranges of different egg types going from off white to pale pink. 

In my personal experience the process of grinding eggshells is quite beautiful. I use a marbled pestle and mortar to grind up the eggshells in the most authentic and basic way but it's time consuming. You should sit down, relax and start grinding it for a couple of hours until it becomes powder.

After you've got the powder (pigment) ready you can make watercolours by mixing the pigment with gum arabic. If you're interested and would love to learn how to make watercolours you may contact us for the next Colour Alchimia workshop. 


Making whiteshell pigment


1 ostrich eggshell or several chicken eggshells


Pestle and mortar
1 glass or plastic container 
Palette knife


  1. If you are going to work with an ostrich eggshell, crush it first in a separate place.
  2. Take the pieces and keep them safe and clean
  3. Grab a piece and put it in the mortar and start grinding it into powder
  4. You may use a sieve if you want to separate the coarse particles from the very fine ones.
  5. Collect the powder with a brush and keep it in a container
  6. You should repeat the process with all the other pieces from the ostrich eggshell
  7. If you want to work with chicken eggshells, you should first clean the shells and let them dry for about two days.
  8. Once they are dry, start crushing and grinding them.
  9. Then you will have two types of whiteshell pigments ready to be used
  10.  You will notice the beautiful colour shades of the pigments

Photos: Kkgas, Studio Laura Daza, Elsa Yranzo, Andrea Costa