STANDING TALL: PLAINS INDIANS ENJOYED HEIGHT, HEALTH ADVANTAGE. COLUMBUS, Ohio - Equestrian Indian tribes on the American Plains in the late 1800s were the tallest people in the world, suggesting that they were surprisingly well-nourished given disease and their lifestyle, a new study found.
Limestone often contains variable amounts of silica in the form of chert (chalcedony, flint, jasper, etc.) or siliceous skeletal fragment (sponge spicules, diatoms, radiolarians), and varying amounts of clay, silt and sand (terrestrial detritus) carried in by rivers.
BACKGROUND: The primary mineral in limestone is calcite or calcium carbonate ( CaCO3). When carbon dioxide ( CO2 ) reacts with water, carbonic acid is produced, see BUBBLES IN YOUR. WATER ACTIVITY. When an acid, such as carbonic acid, reacts with limestone, the limestone.