A pulsar (short for pulsating radio star) is a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation.
Tourmaline is the most colorful of all gemstones. It occurs in all colors, but pink, red, green, blue and multicolored are its most well-known gem colors. Scientifically, tourmaline is not a single mineral, but a group of minerals related in their physical and chemical properties.
An interesting form of multicolored tourmaline, adequately called Watermelon Tourmaline, has a red center surrounded by a green outer layer (or vice versa). When used as a gem, Watermelon Tourmaline is green on one side and red on the other. Schorl, a common black Tourmaline, is fairly inexpensive.