One of the lesser known gemstones, Ametrine (also sometimes known as Trystine) combines the purple hues found in Amethyst with the bright gold colors of citrine, displaying both of them at the same time in a bi-color gem.

For those that like the sound of this, the bad news it that it does not come cheap! There is only one Ametrine mine in the entire world - the Anahi Mine in Bolivia - and as usual, the increased rarity of the stone means vastly increased prices. This country of origin has also lead to another name for the gem - Bolivianite.

Ametrine mining became famous in the 17^th century, when a Spanish conquistador received the Bolivian mine as a present for marrying a local princess, Anahi. The conquistador then proceeded to give gifts from his mine to the Spanish queen, and as a result the gems found their way into Europe for the first time.

Ametrine is usually faceted in a rectangular shape, and displays an almost exact 50/50 ratio of citrine and amethyst colors. This is due to the differing oxidation states of iron within the gem, which occur due to differing temperatures across the stone during the period when it is formed. Other color mixes can also be found, such as gold-blue or green-yellow, but these do not exist naturally and are synthetic versions.

Occasionally a ‘checkerboard’ pattern of facets is included to the top of the gem, increasing the reflection of light. It is also possible to blend the colors, meaning peach and light orange tones can appear in addition to the gold and purple. This makes the gem popular with artistic cutters, who carve and manipulate these hues to create landscape images in the stone.

Various sizes and shapes of Ametrine can be found, and its high level of durability makes it suitable for almost all types of jewelry. The striking color contrast is most visible in gems of over seven carats - but unsurprisingly these do not come cheap.