History and General Information About Natural Ametrine Gemstone

This beautiful purple gold stone, which combines in itself the colors of the amethyst and the citrine, is one of the oldest gemstones known to man. The ametrine gemstone first received attention when a Spanish conquistador got some mines, as a dowry when he married the princess Anahi of the Ayoreos tribe in Bolivia. Upon seeing the beautiful double colored stone and recognizing that it would win him favor at the royal court, he conquistador presented it to the queen. Since then, the ametrine gem became a part of the suite of gemstones, favored by royal ladies and those with wealth. The ametrine gemstones comes into being when both amethyst and citrine occur in the same quartz crystal, and in proximity to each other, to give the effect of two colors.

Chemical Composition of Ametrine Gemstone

Its formula is represented as SiO2, and its color is the result of iron impurities.

Physical Properties of Ametrine Gemstone

The ametrine gemstone is a hard stone measuring 7on the Moh’s scale, with a refractive index of 1.54-1.55 and birefringence of -0.009. Its specific gravity is 2.65. It has no cleavage. It shows conchoidal fracture and has a vitreous luster.

Cut

Ametrine has its greatest color impact in the rectangular shape, when both the colors are highlighted. Innovative cutters add a checkerboard pattern on the facets on the top to increase reflection. Roughs which show a clear transition from purple to yellow are most sought after since on being cut they will reveal both the colors.

Clarity

The color in the ametrine is the result of the iron impurities and the unique color combination of the ametrine results from this. The iron impurities, when they undergo oxidation into different states, create the double color effect. It ranges in clarity from transparent to translucent.

Carat

Being a bicolor stone, for an ametrine to reveal its full beauty, the stone must be of a big size. The colors of ametrine are seen at their best in stones over seven carat.

Color of Ametrine

The ametrine is a combination of the two shades, yellow and purple, which occurred as two separate bands but in a single stone. Expert cutters have been known to cut the stone in such a way so that a landscape is created without altering and addition of any extraneous material.

Price of Ametrine Gemstone

The ametrine, in spite of its rare availability is an inexpensive stone and pieces can be bought for as little as $10. Thus even a stone weighing more than 10 carats can be purchased for anywhere between $20- $100.

Producers

The ametrine comes from the Anahi mine in Bolivia, the oldest and only source of this gemstone, while few stones come from Brazil too, but they are not of the same quality.

Simulants

Ametrines are being produced commercially, in Russian laboratories and they are readily available on the market.  Ametrine is also enhances by heat treating natural amethyst and changing the oxidation state of the iron, while at other times irradiation is used to bring about change in the color of the amethyst.

Interesting Trivia and Other Ametrine Facts

Due to its dual color, the stone is considered to be a talisman that balances the opposing forces of nature and bridges the divide between the material and the spiritual world. The purple amethyst part of the stone helps one to visualize the future he seeks, while the yellow citrine color pushes one towards making this goal a reality. The ametrine brings to its wearer a feeling of calm and peace. It removes negativity and is a tension reliever. This could be on account of its oxygenation capability.

The twin colors in this single stone are the result of the differing oxidation of the iron present in the crystal Geologists put forth the theory that due to a deep vent in the Anahi mines, a certain amount of heat, flowing in the right direction resulted in one area being hotter than the other. These conditions were perfect for the amalgamation of color in the crystals.