Working with casein paint

Armour scales painted red and laced together in rows

Analysis of the scales from Tutankhamun's armour showed they had been stained red on their faces and along their edges.  Exactly what was used to colour the scales is unknown, so I used casein paint, which is known to have been used in ancient Egypt, and is appropriate for painting vegetable tanned leather.  It's also readily available in the 21st century, and if you shop around online you can sometimes get it reasonably cheaply.  This is the same paint people use on furniture to get the shabby chic farmhouse look.  Initially I had planned to use a synthetic leather stain, but that stuff's not cheap and after a bit of thought I figured why not do it properly and use something that was actually available to the ancient Egyptians?

Apparently, some of the objects in Tutankhamun’s tomb were painted with casein paint, but there's no guarantee it was used to paint his armour scales.  Egyptian paint technology was sophisticated, with a wide range of pigments and binders available.  I chose casein purely because it's readily available and convenient; the stuff I got comes in powder form, and just needs to be mixed with water to create a vibrant red paint in any consistency you like.  The directions on the packet suggest mixing it 1:1 with water, but I used a tablespoonful to every 60mls (2oz) of water to get a stain that would soak into the surface of my leather.  As you can see, the result is a rich blood red colour.  Unfortunately the texture doesn't photograph well, but it's a really lovely velvety matte effect.  This is a characteristic of casein paint, and some artists like to use it for this reason.

Be aware, however, that casein paint is finicky to work with.  You'll need to apply two or three coats using quick, even, vertical brush strokes and you may get some streaks of unabsorbed pigment on the surface of the leather, but these can be rubbed off with a damp cloth.  If you use it to stain leather the way I did you will get some variation in colour because not every piece of leather absorbs the same amount of stain and, unlike modern synthetic leather stains, casein paint is not designed to create an even, consistent colour on leather.  If you need a perfectly uniform colour throughout, casein paint is not the product for you.  In this instance I like the naturalistic, variegated effect, but it's something to keep in mind.