Common Mineral Types Are Rose, Amethyst, Citrine
Puzzle 3 of City Nicknames Hard Pack
Question is: Common Mineral Types Are Rose, Amethyst, Citrine
and the answer is: QUARTZ
Word Meaning:
QUARTZ — (mineralogy) The most abundant mineral on the earth's surface, of chemical composition silicon dioxide, SiO₂. It occurs in a variety of forms, both crystalline and amorphous. Found in every environment.
Definitions from Wiktionary.