Practice problem
Which of the following minerals are different varieties of quartz?
Amethyst
Olivine
Hornblende
Sodalite
Rock crystal
Plasma
Tiger's eye
Topaz
Flint
Beryl
Chert
Agate
Calcite
Chalcedony
Microcline
Jasper
Oligoclase
Tourmaline
Opal
Type a concept, like “slope” or “photosynthesis”.