Facts About Silicon

Regardless the fact that silicon represents 27.2% of the mass of the earths crust and is after oxygen (with 45.5 mass %) the second most abundant element its extremely rare to be found in nature in its elementary pure form.
Its always bound to oxygene in form of its oxyde SiO2 which is quartz or in the form of silicates like feldspar, mica and hundreds of other silicate minerals.

Sand and sand stone are also (mostly) made out of quartz. Also artificial "stones" like bricks, pottery or concrete contain vast amounts of silicon in the form of quartz and silicates.
Its also found in the human body and in most plants.

Rough metallic silicon is produced from silicon oxide (which is quartz or just "sand") by heating with coal in an electric furnace. Hence there is plenty of quartz all over the planet there is no way that we ever will run out of silicon.
However production of silicon consumes a lot of energy and coal at the first place, which is the main price factor for rough metallic silicon.

Producing semiconductor electronic grade silicon with a mimum 99.9999% purity from rough silicon is a higly sophisticated time and energy consuming process which can only take place in huge and expensive plants which are run by a special trained workforce.
Within in the last few years the production of high quality silicon for the electronic industries or solar cells has always been a bottle neck, as the demand grows faster then the supply.
New high purity silicon factories take a huge investment, a long time to build  and need a highly trained workforce.
So sudden price increases for pure electronic grade silicon are quite common.
This is also the reason that almost no high grade silicon material leaves the production cycle and is sold to third parties or the public.

Silicon melts at 1420 °C (2588 °F) and vaporizes at 3280 °C about (5936 °F).
The hardness is 7 after the Mohs hardness scale which is the same like quartz, so silicon is not likely to get scratched.
Its shine and the slightly blue metallic color are stable at the air and it also withstands most acids.
There are no allergies known with solid metallic silicon.

Silicon cut for jewelry purposes looks a little bit like hematite or its artificial counterpart "hematine". Rough pieces also may resemble a little bit to galenite.
However the high hardness and the low specific weight of 2,336 g/cm3 make it easy to distinguish it from other materials.
Silicon will form crystals in the form of an octahedron and has exactly the same crystal structure as diamond.
Silicon will transmit infrared light and is used to make lenses and prisms for infrared optics.

Due to his unique properties and due to its relation to the element of life, carbon, silicon is regocnized in the esoteric world, regardless the fact that it has to be produced artificialy in its pure metallic form.