Ulexite

Ulexite from Morocco is an ore of boron and is studied for its unique optical properties. Also known as the Television Stone, it is made up of thin, parallel, sheet-like fibers. When the specimen is polished at the top and bottom, each fiber transmits light through it, causing anything underneath it to appear as if it is at the top. Ulexite is highly popular among mineral collectors.

Average dimensions: L 2" x H 1" x W 1", Average weight: 0.07 lb.