Quartz which occurs in bands of yellow and purple has been given the name of Ametrine(amethyst + citrine). Originally discovered in Brazil, the world's current supply comes from one area in Bolivia. The ametrine crystals from this mine often exhibit an abrupt color transition, which probably reflects dramatic changes in temperature during their formation.
Ametrine is a bicolor purple and yellow variety of quartz often used as an ornament. There are pear, emerald cut, square, trillion, round, oval, cushion, and heart shaped cut ametrine gems in many beautiful and unique color patterns. Clarity and good size make it a favored material of gem carvers and cabochon artists as well. For lovers of amethyst and citrine, ametrine is a must for any collection.
The prices, uses and value of ametrine vary tremendously, depending on the size and quality of the gemstone.
Why Buy Loose Gemstones Instead of Pre-Set Jewelry?
There are many reasons, but basically it boils down to value and choice...
When buying your ametrine gemstone loose instead of a pre-set stone, you can be sure you are getting the best value for your money. Loose gemstones are less expensive, a better value, and you can really see what you are paying for. The most important part of getting the right price and finding the best value is to first see what you're getting. A jewelry setting will hide the inclusions inside a gem, and can deepen or brighten its color. With a loose stone you can much more easily inspect the gem and see it for what it really is. In this way you can get a better idea of its true worth and be sure you are paying a fair price.
The second advantage of buying a loose gemstone is choice. You are free to pick the exact color, cut, shape and variety of the stone for the setting of your dreams, be it yellow gold, white gold, platinum or silver; prong set or bezel set with diamond accents. You can experience the joy of creating your very own, one-of-a-kind jewelry design. Choose from a variety of jewelry settings and styles to create a completely original presentation that will perfectly suit your individual gemstone and will be as unique as you are!
|Bicolor mix of purple and yellow, orange or golden brown.
|1.544 - 1.553
|2.6 - 2.7
Quartz varieties are commonly separated into two groups based on the size of the individual grains or crystals; macrocrystalline quartz in which individual crystals are distinguishable with the naked eye, and cryptocrystalline quartz in which the individual crystals are too small to be easily distinguishable under the light microscope.
Some of the macrocrystalline quartz varieties are: Amethyst, Ametrine, Cat's-eye Quartz, Citrine, Phantom Quartz , Rock Crystal, Rose Quartz, Rutilated Quartz and Smoky Quartz. Blue Aventurine Quartz and Green Aventurine Quartz are actually quartzites (a rock, not a mineral) composed essentially of interlocking macrocrystalline quartz grains with disseminated grains of other color imparting minerals.
The cryptocrystalline varieties of quartz may be separated into two types; fibrous and microgranular. Chalcedony is the general term applied to the fibrous cryptocrystalline varieties. Agate is an example of a fibrous cryptocystalline banded chalcedony variety of quartz. Carnelian, Chrysoprase and bloodstone are other chalcedony varieties. Chert is the general term applied to the granular cryptocrystalline varieties of quartz, of which flint and Jasper are examples.
Iron atoms may enter the crystal structure of quartz as an impurity in a number of sites and in different oxidation states. For ametrine to occur, iron impurities in the Fe4+ oxidation state must be present in the specific color producing sites in a portion of the quartz and Fe3+ must be present in the specific color producing sites in another portion of the quartz. There are a number of processes by which iron can be present in more than one oxidation state in different parts of the same specimen, and they are not all fully understood.
Ametrine has a chemical formula of SiO2, a density of 2.60 - 2.70, and a refractive index of 1.544 - 1.553. The refractive index (RI), measured using a refractometer, is an indication of the amount light rays are bent by a mineral. Birefringence is the difference between the minimum and maximum RI. When birefringence is high, light rays reflect off different parts of the back of a stone causing an apparent doubling of the back facets when viewed through the front facet.
Most gems have a crystalline structure. Crystals have planes of symmetry and are divided into seven symmetry systems. The number of axes, their length, and their angle to each other determine the system to which a crystal belongs. Ametrine gemstones belong to the Hexagonal crystal system.
The name Ametrine was coined for a member of the Quartz family which displays a combination of both Amethyst and Citrine. Natural Ametrine first arrived in the market in 1980 when it was discovered at the Anhai mine in Bolivia. This mine became well- known when a Spanish conquistador received it as a dowry when he married a princess from the Ayoreos tribe in the seventeenth century.
Ametrine is said to aid meditation, to calm and relieve tension, and dispel negativity .
Ametrine is a type of naturally occurring quartz. It is made from a mixture of Amethyst and Citrine. It should be noted that Citrine is Amethyst that has been super heated. Ametrine is sometimes referred to as Trystine or even by its commercial name Bolivianite. Ametrine comes from mines in Bolivia, where practically all of the worlds Ametrine are located.
Since Ametrine is extremely rare, it doesn’t have as an extensive history and origin as other popular gemstones; however Ametrine was said to be first introduced in Europe by Conquistadors that found Ametrine in South America. It is said that Ametrine was given to the Spanish Queen as a gift for a dowry.
Ametrine has only been commercially available for a little more than 25 years. It first was sold commercially in 1980, when Ametrine was put on the market by the Anahi Mine in Bolivia.
Because there is little history about this precious and beautiful stone, most people usually look towards the two minerals present in Ametrine – Amethyst and Citrine. This means that Ametrine can relieve stress and make one feel calm. It can also make one enhance their thought process and mental capabilities.