What is Genuine Mother-of-Toilet-Seat?

Gibson 1938 fingerboard
Gibson 1938 Headstock or Peghead

Stewart-MacDonald's fancy pearloid - laminated
When I revealed that the second Tickler Ukulele would have a fingerboard made of genuine mother-of-toilet-seat, I realized that some people might not know what that is. It's a plastic that looks like mother of pearl and it's also known as pearloid. On certain vintage models of guitars, banjos and ukes, it was used for pickguards and fingerboards. It was also used to decorate banjo resonators and headstocks. Lou Reimuller (luthier of Tickler Ukes) bought his pearloid at Warmoth where they have all colors and patterns. They also have supplies at Stewart-MacDonald.
Here is a Gibson 1938 from the
National Music Museum Collection
at the University of South Dakota.

The Art of Amy Crehore