Ulexite

Ulexite, also known as "TV rock," is a white, fibrous borate mineral (NaCaB₅O₆(OH)₆·5H₂O) famous for its unique ability to act as a natural fiber optic, transmitting images from one side to the other due to its parallel, transparent fibers.

Via: Ulexite stone is a mineral, it is not transparent but yet it projects an image of what ever is behind it onto its surface. https://x.com/sciencegirl/status/2010444637325205735