The poly-crystalline form of this element is made by the Siemens process.
The poly-crystalline form of this element is made by the Siemens process. Berzelius discovered this element by heating its tetra-fluoride with potassium metal. A common reference compound for proton NMR contains four methyl groups surrounded by one atom of this element. Found directly below carbon on the periodic table, this element is the second most abundant in Earth's crust. The mineral quartz is composed of oxygen and this element. For 10 points, name this chemical element that names a valley in California home to many companies in the semiconductor industry.
The poly-crystalline form of this element is made by the Siemens process.
{silicon} [prompt on "Si"]