Most igneous rocks (the kind of rocks that form major mountain ranges like the Sierras and the Rocky Mountains) have a lot of quartz and feldspar and relatively little of the others (especially diamond, which together with its hardness and cleavage properties makes it so valuable).
(rocks; form; major mountain ranges like the Sierras and the Rocky Mountains) (Most igneous rocks; have; a lot of quartz and feldspar and relatively little of the others) (especially diamond; makes; it so valuable)
rocks Most igneous rocks especially diamond
form have makes
major mountain ranges like the Sierras and the Rocky Mountains
a lot of quartz and feldspar and relatively little of the others
it so valuable