Quartz

Quartz 

Macro Crystalline Quartz: The crystals are visible to the naked eye. This Group includes AmethystAventurineRock Crystal, Blue Quartz, CitrineHerkimer DiamondSmoky QuartzRose Quartz.

Micro crystalline quartz: The crystals are only visible with the microscope. This group includes AgateCarnelian, ChalcedonyChyrsopraseHeliotrope (Jasper), Jasper

Other Gemstones belonging to the Quartz Group include: AmetrienAmethyst QuartzWoodstone (petrified wood)