Coarsely crystalline varieties of silica—
Rock crystal: Colorless
Amethyst: Purple
Citrine: Yellow to amber
Morion: Black
Smoky quartz or cairngorm: smoky gray to brown
Rose quartz: Translucent pink
Green quartz or praziolite: Green
Cryptocrystalline varieties of silica—
Chalcedony and Jasper (variable)