A fine-grained, extrusive igneous rock, having parallel mineral composition with granite
A fine-grained, extrusive igneous rock, having parallel mineral composition with granite
A shaft or room that has been excavated from the ground upward
A heavy, dense and rare, silvery-white precious metal. Symbol, Re
The heaviest radioactive gas element, symbol, Rn
A tetragonal mineral and ore of titanium, TiO2
A silvery white, hexagonal platinum group metal. Symbol, Ru
Water that drains from a flood plain, or higher structure into streams, rivers, or other channels
The red, gemstone variety of corundum Al2O3. Sapphires represent the blue variety of the same substance
A soft, silvery-white, metal. Symbol, Rb
A loose mass of rock fragments