Ulexite has a very unusual property: it acts as a fiber optic cable. This is because its crystal structure is composed of fibers that are aligned parallel to each other. These fibers can transmit light along their length, just like a fiber optic cable.

This unique property gives ulexite the nickname "TV rock" because if you place a piece of ulexite over an image, the image will appear magnified and projected onto the surface of the mineral. This effect is due to the light being transmitted through the fibers and then refracted out the other side.

So, while most minerals are opaque or translucent, ulexite's fiber optic nature makes it a truly unique and intriguing material.