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Monazite

/ˈmɒnəzaɪt/noun

A reddish-brown phosphate mineral of cerium and other rare earths, the main commercial source of thorium.

The Greek roots

μονάζω
monázō
to be solitary
+
μόνος
mónos
alone, single

Literally: the solitary one

The story of the word

Breithaupt named it in 1829 because the crystals turned up singly rather than in clusters. The name aged badly: monazite sand is now dredged by the shipload from beaches in India, Brazil and Australia. Its thorium content makes it mildly radioactive, and its uranium and lead make it one of geology's best clocks for dating rocks.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
19th century

Same family

monkmonasterymonopolymonotone

In a sentence

The heavy mineral fraction was almost entirely zircon and monazite.

Monazite dating put the metamorphism at 1.8 billion years.

Built on the same root

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