Peridot

Sometimes amethyst and citrine colors are found in the same crystal of quartz. These bicolor yellow and purple quartz gemstones are called ametrine. Ametrine is a very durable gemstone suited for a variety of jewelry uses. Ametrine is most typically faceted in a rectangular shape with a 50/50 pairing of amethyst and citrine, though more creative cuts are becoming popular. Ametrine deposits are limited.

Ametrine comes in bands of yellow and purple. The colors only reach a medium level of saturation and are never very vivid (except in synthetic ametrine). Ametrine typically exhibits an abrupt color transition. It looks best in daylight, more precisely, particularly just after sunrise and before sunset, when the light is soft and warm. Ametrine, like most quartz, is typically quite clean with good luster. Ametrine is most typically faceted in a rectangular shape with a 50/50 pairing of amethyst and citrine. Sometimes a checkerboard pattern of facets is added to the top to increase light reflection. Ametrine can also be cut to blend the two colors so that the resulting stone is a mix of yellow, purple, and peach tones throughout the stone. Ametrine is also popular among artistic cutters and carvers who play with the colors, creating patterns in the stone.

The Anahi Mine in Bolivia is the major world producer of ametrine. The mine became famous in the seventeenth century when a Spanish conquistador received it as a present when he married a princess from the Ayoreos tribe named Anahi. Ametrine was introduced to Europe through the conquistador's gifts to the Spanish queen. Other deposits are found in Brazil (Rio Grande de Sul). As of now ametrine hasn't earned any fame. There is the possibility that natural ametrine will become rare due to limited deposits.

Ametrine Gemology
Species: Quartz
Color: Bands of yellow and purple
Chemical composition: SiO2 silicon dioxide
Crystal system: (Trigonal) compact
Hardness: 7 (Mohs scale)
Specific gravity: 2.65
Refractive index: 1.54 - 1.55
Birefringence: +0.009
Color of streak: White
Absorption spectrum: Cannot be evaluated
Fluorescence: None

Ametrine combines the powers of amethyst and citrine in one gem. Therefore ametrine can be the birthstone for those who are born in February or for the Zodiac sign of Pisces.

In Antiquity, as well as in the Middle Ages people believed that the cosmos is reflected in gemstones. Ametrine can be assigned to the planets Jupiter, Mercury, Neptune and Pluto.

The healing powers of gems remain a controversial issue, but are mentioned for centuries by healers, shamans and medicine men. Whether it's a fact or a placebo effect doesn't matter, if it helps. The safest approach is to wear the gemstone in skin contact to the troubled part of the body. Ametrine could be said to be of help for headaches, pancreas and backache.