6.29ct Emerald Cut Ametrine Gemstone - Natural Semi-Precious Stone

This lovely 6.29 caratnatural ametrine exhibits colour zoning of both purple (amethyst) and yellow(citrine).

Ametrine is theperfect stone for someone for whom the months of November and February bearsignificance, since it contains both the official birthstone for February, andthe alternative birthstone for November.

Weight: 6.29 carat
Cut: Step
Colour: Zoned pale yellow & purple
Length: 11.67 mm
Width: 11.10 mm
Depth: 6.70 mm
Origin: Bolivia
Treatment: None
Certificate: No Can be certified at an extra charge.

About Ametrine:

Species: Quartz
Deposits found in: Brazil (Rio Grande do Sul) and Bolivia.
Known colours: A variety of citrine yellows paired with varyingintensities of amethyst purple.
Mohs Hardness: 7

Also known as trystineor bolivianite, ametrine is a colour zoned variety of quartz crystals, whichcontains both citrine and amethyst.

There are only twoknown sources for this unique gem, though most of the commercial stonesoriginate from Bolivia, where it was first descovered in the 1980s.

The zoning occurs dueto temperature changes during the growth of the crystal, with the citrineportions containing oxidized iron, while the iron in the amethyst segmentsremains unoxidized.

Ametrine can becreated artificially by beta irradiation of natural citrine, which itself isoften created from heat treated smokey quartz or amethyst. This sometimesproduces material with greenish yellows or blueish purples. Natural ametrinedoes not exhibit these colours.

The colouring inquartz crystals (even when natural) are sensitive to light, especiallysunlight, and heat, and therefore care must be taken when storing these gems.

Please note: We takegreat care to ensure that the photographs are an accurate representation of theactual stone, but due to differences in screen quality and resolution, and thefact that the colour of a gemstone is dependent on the type of light it isviewed in, some variation is possible.

Stock Code: RM496532