Clues for the word "THALLIUM"

We've had 5 crossword clues used for this word, and seen it 3 times in crosswords. It was last seen in Guardian Prize crossword on May 10, 2014.

Definition of thallium

n. - A rare metallic element of the aluminium group found in some minerals, as certain pyrites, and also in the lead-chamber deposit in the manufacture of sulphuric acid. It is isolated as a heavy, soft, bluish white metal, easily oxidized in moist air, but preserved by keeping under water. Symbol Tl. Atomic weight 203.7.