Peridot is one of the gemstones, the exact origin of which often can be traced by its inclusions. Hair or needle-shaped inclusions of Ludwigite, frequently but understandably misdiagnosed as Rutile, is a sure sign of Pakistani origin. Peridot is one of the few gemstones that occur in only one color: an olive-green. The intensity and tint of the green, however, depends on the percentage of iron that is contained in the crystal structure, so the color of individual peridot gems can vary from yellow to olive, to brownish-green. In rare cases, peridot may occur in a medium-dark toned, visually pure green with no secondary yellow hue or brown mask.