Ulexite is a mineral, also known as TV rock, that is mainly found in California, Nevada, Chile, and Kazakhstan. Its scientific name is hydrated sodium calcium borate hydroxide. It is named after a German chemist G. L. Ulex, who discovered it in the 1800s. Ulexite contains optical fibers that polarize light into slow and fast waves, which can transmit an image to the other side of a rock. Internal reflection of the slow waves and the refraction of the fast waves cause a unique optical effect when held over an object.
Since ulexite is a soft substance and dissolves in water, it cannot be used as a gem for jewelry making. It is also brittle and contains clay particles, which often hinder light transmission. It is white and sometimes lightly colored due to the clay impurities. It often
Ulexite is white to lightly colored by impurities, commonly clay. Its unique optical property is that is transmits light along the long axis of the crystal by internal reflections, very much in the same way as in fiber optics. Clay particles often hinder this light transmission. Ulexite can alter to gypsum and colemanite.
