And the gemstone is as British as it gets. Jet is one of only two gems mined in England — the other being Derbyshire blue john, which resembles amethyst streaked with dark veins and bands.
The gem comes in a range of colors, such as pink, red, green, blue, violet and black. This is fitting since tourmaline's name derives from the Sinhalese word "toramalli," which means "stone ...