Boron (atomic symbol B), a naturally occuring Earth element, was first isolated by Sir Humphry Davy and Joseph Louis Gay-Lussac and Louis Jacques Thénard in 1808. Tourmaline is a boron silicate. Opaque and black in color, tourmaline is a semi-precious stone that can be found in a variety of colors based on the presence of iron, magnesium, or lithium. The dark color indicates this sample is rich in iron.
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