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Roger Weller, geology instructor
by Trevor Ball
Silicon is the 14th element of the periodic table and
the 8th most common element in the universe. While Silicon rarely
appears in a pure state naturally, it is readily found in common materials like
quartz and sand. Silicon is classified as a metalloid, meaning that is neither a
metal nor a non-metal, but something in between the two. In a pure crystalline
state Silicon possess a metallic grey color, is strong but brittle and chips
While Silicon was only discovered in the last three centuries,
Quartz, which is made from Silicon, has been known for thousands of years. In
1789, French chemist Antoine Lavoisier proposed that there was a new chemical
element that could be discovered in quartz and that this element would be very
abundant. It could be said that his claim was an understatement since Silicon is
the second most abundant element in the Earth’s crust at 28%, the only element
larger presence in the crust is oxygen.
There were two potential discoveries of Silicon that followed. In
1808 Englishman Humphry Davy may have isolated partly pure Silicon without
realizing it. Later in 1811, French chemists Joseph L. Gay-Lussac and Louis
Jacques Thénard may have also made impure Silicon through their use of reacting
potassium with silicon tetrafluoride. This created a reddish-brown solid that
might have been amorphous Silicon, but they never tried to purify the substance.
Due to Silicon’s presence in 90% of the Earth’s crust, it has
found a variety of uses over time. Silicon in its most common natural state is
usually used as building materials. This is because Silicon is present in things
such as silica sand, clays, and most types of building stone. Silicates are used
to create building mortar and combined with silica sand and gravel in order to
Another of Silicon’s uses is the creation of glass and ceramics.
Silicon is present in normal glass and whiteware ceramics such as porcelain.
Silica based glass fibers are used to create optical fiber, fiberglass, and
While the previous examples were all for uses of Silicon in its
natural state there is a very important role pure Silicon plays in modern
society. When in an extremely pure state Silicon can be doped with Arsenic,
Boron, Gallium, or Phosphorous to produce Silicon for use in solid state
electronics such as rectifiers, solar cells, and transistors which have an
important place in modern electronic and space age industries.
While Silicon is readily abundant, there are very few species that make a great deal of use of it. Both fresh and salt-water diatoms use Silicon extracted from the water to create their cell walls and skeletons. The biggest use Humans have for silicon is the aorta, the primary artery of the human body. Silicon is needed to synthesize elastin and collagen, and the Aorta has the highest concentration of elastin and silicon in the human body.