Ulexite

Part of speech: noun

Pronunciation: /juˈlɛkˌsaɪt/

Definitions

1. A naturally occurring mineral composed of hydrated sodium calcium borate, often found in sedimentary deposits
2. This mineral, characterized by its fibrous structure, is known for its optical qualities and is used in certain industrial applications
3. Commonly referred to as "TV rock," it exhibits unique light transmission properties making it valuable for specific optical uses

Etymology: Ulexite is named after Georg Ludwig Ulex (1811–1883), a German chemist who worked on the mineral's chemistry, and the name was given to the mineral in his honour. The "-ite" ending is the standard suffix mineralogists attached to mineral names, from the Greek "lithos" (stone) through Latin, so the word is a person's name with a conventional label added. The mineral itself is a hydrated sodium calcium borate that grows as soft, silky fibres, and it is known for a striking optical effect: when a polished slice is laid over text, the fibres act like tiny light guides, so the print appears on the upper surface. This is why it is sometimes nicknamed "TV rock", a joke that depends on the fibres transmitting an image rather than on anything to do with the word's origin.