TRIDYMITE

noun

15 Scrabble

15 WWF

T 1

R 1

I 1

D 2

Y 4

M 3

I 1

T 1

E 1

Definition

A rare mineral of volcanic rocks that solidified at a high temperature, with the chemical composition silicon dioxide, SiO2. Tridymite is chemically identical to quartz, but has a different crystal structure. Sometimes contains sodium aluminum silicate, which seems to be expelled when quartz solidifies at lower temperatures.