Kind sorts earth materials into their broadest category, such as mineral, rock or sediment. Wikipedia describes quartz as "a hard mineral composed of silica (silicon dioxide)," placing it firmly in the mineral kind rather than among rocks made of many minerals together. This dimension gives a visitor the widest possible grouping of what a material actually is.
Rock
Filter Results56 entries
Reader Challenges (0)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.