Quoted from Chippewa-Pin:What is the playfield made of on Jolly Park and Verne's World (Spinball) ? Seems like there's a clear hard plastic layer. Maybe it's on top of wood.
It’s a 1/4” layer of reverse-printed Perspex on top of MDF. I’ve had a lot of games with these playfields and I love them. INDER, Spinball, SLEIC and some other Spanish companies used them.