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Sand Fiber optics and computer chips are
made from silicon. Silicon's base component is sand.
Hourglasses
and other devices utilizing sand were clocks in Ancient
Egypt and in the Middle Ages. The British Navy used
hourglasses as late as 1839 for approximate timekeeping.
Standard equipment included an hourglass, a half-hour
glass, and an eight minute glass. Timing devices using
sand are still in common use today; they are used as egg
times and in board games.
In some deserts, sand dunes make mysterious music.
Studies show that sand grains in musical dunes are
especially smooth. As sand slides down the dune, the
motion makes low booming sounds similar to the sounds of
drums and bass fiddles.
Sand on the beaches of Florida's Panhandle region
sparkles white because it is nearly pure quartz.
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Asphalt
In 1876, Pennsylvania
Avenue was one of the nation's first asphalt
paved roads.
In 1498,
on his third voyage exploring the New World, Columbus
wrote in the ship's log about stopping in Trinidad and
using their natural asphalt reserve to waterproof and
caulk his ships.
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Stone
The Grand
Coulee Dam in Washington State required 17
million tons of aggregate in its construction.
The Denver
International Airport outside of Denver,
Colorado, required 5 million tons of aggregate in its
construction.
There
is enough concrete in the Sears Tower,
Chicago, IL to pave 8 one-mile lanes of interstate
highway.
The tower has 110 stories, sits on
two city blocks and rises one quarter mile (1,454 feet)
above the ground.
The
faces on Mount Rushmore
and Stone Mountain's
Confederate Memorial are carved into granite.
Birds eat small bits of
crushed stone to help them digest the foods they eat.
In an underground coal
mine, the walls of the tunnels or shafts are white, not
black. They are usually covered with a white rock dust,
usually powdered limestone, which settles coal dust.
Nature’s rust, Goethite, formed by weathering
iron-bearing rocks, was sought by Native Indians for face
paint.
The ancient Romans used pumice mixed with lime as a
cementing material.
The Egyptian pyramids
are made from limestone.
The first tool is
believed to have been the "pebble tool" -- a
fist-sized rock with a sharp edge.
Some animals use simple rocks to help them get at their
food. Otters use rocks to break open clam shells. Some
birds fly over eggs, dropping stones to break them open.
Australian aborigine people used quartz in a magical
ceremony to make rain fall. They broke crystals of quartz
into tiny bits that looked like raindrops, then poured
showers of these "raindrops" over one another
in hopes this would trick real rain into falling.
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