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Amazonite | Blog


Amazonite crystals at Sotheby’s

Description of Amazonite

Formula (K,Na)AlSi3O8
Molecular mass
IMA Status
Systematics according to IMA (Mills et al., 2009)
Class silicates
Group Feldspars
Physical Properties
Color Light blue-green
Dash color White
Shine Glass
Transparency Shines through the edges
Mohs hardness 6-6.5
Cleavage Perfect by (001) and (010)
kink stepped
Density 2.54 – 2.57 g/cm³
Crystallographic properties
space group
Syngony Triclinic
Optical properties
optical type
Refractive index 1.514-1.539
Birefringence 0.007-0.010
optical relief
Dispersion of optical axes
Pleochroism Missing
Luminescence Weakly luminous yellow-green (LW), absent (SW)

Amazonite stone is a green mineral named after the Amazon River in South America.

This green mineral is known by two names: Amazonite or Amazonian stone. Technically, this stone is a green tectosilicate mineral composed of a microcline. The formula of this mineral is K(AISi3o8).

This mineral belongs to the triclinic syngony.

Why is Amazonite named after the Amazon River?

The name of this mineral is somewhat misleading. The reason this mineral is named after the Amazon River in South America is because green stones have been found in the Amazon region in the past. However, it is still not decided whether green feldspar is actually found in this part of the world.

Where is it mined?

So where is Amazonite mined? The first thing to say is that Amazonite has a limited distribution. The largest former source of amazonite was in the Ilmensky mountains in the Southern Urals in the administrative territory of Russia, known as Miass. Amazonite is found in granite rocks in that region of Russia near Chelyabinsk.

Amazonite stones have also been found in such remote regions as the Tibesti mountains in Jebel Aegei in Libya, North Africa and the Baishitouquan granite intrusion in the Xinjiang area in China, Asia.

But in recent years, some areas of North America have become famous sites for the occurrence of amazonite. Pikes Peak, Colorado, has become one of the main sites characterized by the fact that amazonite or Amazonian stone found there is associated with albite, orthoclase, smoky quartz and pegmatite. But this mineral is also found elsewhere in the US, such as the Morefield Mine, Virginia or Crystal Park in El Paso County, Colorado.

How can amazonite be identified?

The main characteristic of this tectosilicate mineral is its color, which has shades between green and blue-green. When polished, this mineral appears bright green, which is why it is often used as a relatively cheap gemstone. The only downside to using amazonite this way is that it can crack easily, and on the other hand, it can easily lose its luster because it is a relatively soft stone. Amazonites often crack or chip easily, so they should always be handled with the utmost care.

But amazonite or Amazonian stone can be identified by many other characteristics that are not its green or blue-green color characteristics.

Let’s now look at other characteristics that would allow us to identify this mineral:

  • The crystalline habit of this stone is prismatic and its cleavage is perfect.
  • The fracture characteristic of amazonite is uneven and splintered. And its tenacity is characterized as fragile.
  • Amazonite has a hardness scale of 6-6.5 on the Mohs mineral hardness scale. The luster of amazonite is glassy, ​​the band is always white.
  • But what about its transparency? Amazonite stones are translucent or opaque.
  • Amazonite has a specific gravity of 2.56-2.58. The refractive index of Amazonite stones is between 1.522 and 1.530. And its birefringence is -0.008.
  • Pleochroism in amazonite is completely absent, and also has no dispersion. Finally, ultraviolet fluorescence is weak and olive green in color.

Russian carved amazonite cup with silver gilt and gemstone setting, circa 1900

Where is it used?

As we have already pointed out, amazonite is used as a relatively cheap gemstone. But we didn’t say what this gem was used for. Polished amazonite is most often used in beads.

Polished amazonite or Amazonian stone is also sometimes used in ornamental carvings and cabochons (i.e., as a gem that has been polished but not cut).

It is also important to note that, unlike other gemstones, amazonite is never processed or improved.

There are other similar stones that can sometimes be confused with Amazonite or Amazonian stone, such as aventurine and jade. But there are some clear differences between these three stones.

For example, aventurine has a sparkle effect that microcline stones like amazonite do not have. And jade is glossier than Amazonian stone and lacks the white streaks that are mixed with Amazonite. Of the two stones (Aventurine and Jade), Jade is by far the hardest stone.

Amazonite head of a Vestal Virgin, Italy, 18th century.

Amazonite head of a Vestal Virgin, Italy, 18th century.

Silver, marcasite and amazonite necklace designed by Gustav Brandle for Farner

Silver, marcasite and amazonite necklace designed by Gustav Brandle for Farner

Brooch-clip with precious stones. Stylized motif design with carved jade, citrine and amazonite, 10 diamonds and enamel accents.

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