A member named Stan Bult started recording clown images on chicken eggs with the insides blown out. It started as a hobby, and, like many hobbies, it just grew. The collection continued to be lent out after Mr. Bult's death but sadly most of the eggs were destroyed in an accident at one such exhibit around 1965.
Clown Bluey became chairman of Clowns International in 1984 and resurrected Mr. Bult's practice of recording clown members' faces on eggs. This time a professional artist was used and the faces were painted on china-pot eggs instead of chicken eggs. Over the years, many of the lost older eggs have been reproduced, and new eggs are added frequently.
The eggs are a miniature portrait. In addition to paint, the artist uses samples of the clown's costume material and wig-hair to produce an exact match. A photo of the egg collection may be seen at the Clowns International website. LINK
Here is a sample egg of Emmett Kelly.
Leon "Buttons" McBryde heard about the British practice of registering clown makeup using eggs. He and his wife Linda eventually met the caretaker of the British clown egg registry, and started a similar registry for clowns in the US. This collection shows clowns of all types from around the world. It grew to contain thousands of eggs, and became an almost official way to lay claim to a unique appearance. There is at least one documented court case where the egg was involved to prove intellectual property of a pilfered make-up design. I have to stop clowning around and get back to work.