Tourmaline is also known as tourmaline. The English name Tourmaline is derived from the ancient Sinhala (Ceylon) word Turmali, which means "mixed gemstone". Legend has it that the origin of tourmaline is in 1703 AD. Several children in Amsterdam, the Netherlands, were playing with the stones brought back by Dutch voyagers. They discovered that in addition to the strange colors that appeared in these stones under the sun, they were even more surprised that these stones had an ability to attract or attract people. It repels light objects such as dust or grass clippings, so the Dutch call it limestone. It was not until 1768 AD that the famous Swedish scientist Linnes discovered that tourmaline also has piezoelectric and pyroelectric properties, which is the origin of the name tourmaline. Until now, tourmaline is often used in science to measure luminous intensity and pressure changes. At the beginning of World War II, it was the only substance that could determine the pressure of nuclear explosions. Now, it is widely used in the optical industry.