Amethyst Gemstones, King's Purple Gems

January 30, 2017

 

Amethyst Gemstones, King's Gems.

Beautiful and sober purple variant quartz. Amethyst gems are present in myths and symbols.

From the Greek word AMETHYSTOS (not intoxicated), it evokes the color of the wine to which water has been added to limit their negative effects.

Violet amethyst is the "sister gemstone" of yellow citrine. Ametrine is the combination of amethyst and citrine, with its typical color-zone. 

Contens

  1. Amethyst Color
  2. Cut and Sizes of Amethyst Gemstones
  3. Clarity and Typical Inclusions of Amethyst
  4. Amethyst, Genesis and Origin
  5. Enhancements and Synthesis
  6. Amethyst, Myths and Legends
  7. February Birthstone, Amethyst Gemstone
  8. General Description and Optical Properties of Amethyst

 

AMETHYST COLOR

Back to Top

Amethyst gemstones are the gems most commonly associated with the color purple. The purple color can be bluish or reddish with grade of saturation from grayish / brownish to vivid.

The biggest factor in the value of the Amethyst Gemstones is the COLOR

Amethyst Gemstones commonly show color zoning, consisting in angular zones of darker to lighter color. The color of amethyst is  caused by the presence of color centers and iron.

The highest grade amethyst color have a rich velvety slight bluish purple with red and blue flashes commonly called “Siberian Amethyst” or “Deep Siberian Amethyst” (these terms refer to the color, not the origin).

They are also highly valued the amethyst color strong reddish purple without color zoning and without brown hue. 




 

 

AMETHYST, CUT & SIZES

Back to Top

Amethyst cut stones are available in a wide variety of shapes. Apart of convencional cut, we can find fancy cuts as customer taste.

Until 18th Century was included in the most valuable gemstones,  until the discovery of extensive deposits. The effect that large sizes has on the price of amethyst gemstones is less than other gemstones. 

As amethyst were reserved for ROYALTY, we can find Amethyst Gemstones in the British Crown Jewels or on the Swedish Crown Collection.
We can find big CRYSTALS of Amethyst Gemstones in Texas Memorial Museum (amethyst geode of 250 pound) and GIA Museum exhibits a 164 pounds crystal.

 

CLARITY & INCLUSIONS

Back to Top

Amethyst Gemstones  will show eye-visible inclusions 

 

Typical inclusions: The main inclusions in amethysts are the called “zebra stripes”, primary fluid inclusions  describing the faces of the rhombohedron.

 We also can find “color zoning”  angular zones of darker and lighter color, and Brazilian Law Twinning. 

Two-phase inclusions. Solid Inclusions.


  

GENESIS & ORIGIN

Back to Top

GENESIS: Volcanic igneous rocks and pegmatites. Geodes. Alluvial deposits.

Amethyst gemstones are found: Afghanistan, Bolivia, Brazil, Burma (Myanmar), Canada, Cambodia, India, Kenya, Madagascar, Mexico, Namibia, Nigeria, Peru, Russia, South Korea, Sri Lanka, Uruguay, Usa ...  

 

ENHANCEMENTS AND SYNTHESIS OF THE AMETHYST

Back to Top

               ENHANCEMENTS:

Heated at 450  C losses its violet color and turns yellow - orange  and then resemble the citrine. The original color can be restored by x-ray radiation. 

SYNTHESIS:

There are many synthetic amethysts in the market.
If the gem does not have the typical inclusions of synthesis, it is difficult to detect with conventional methods.

 

 

MYTHS & LEGENDS  AMETHYST

Back to Top

The Romans drank in cups of amethyst to protect themselves against the effects of wine and Christian bishops wear ame-thyst rings referring to the sober state of the Apostles on Pentecost (Acts 2:15).

 

Belleau, the poet, gives life as the chaste maiden who does not succumb to the charms of Bacchus and whom Diana becomes the white stone, sprinkled by the repentant wine Bacchus.

 

Saint Valentine wore an amethyst ring with the image of Cupid.


 

FEBRUARY BIRTHSTONE, AMETHYST GEMSTONE

Back to Top

Amethyst gemstones are the birthstone of February, for Pisces, and for the 6th anniversary of marriage.

More information about Birthstones.

 

GENERAL DESCRIPTION PHYSICAL & OPTICAL PROPERTIES OF AMETHYST

Back to Top

 



Inclusions in Amethyst

Zebra stripes. Liquid inclusions

Inclusions in Amethyst Stone

Interference fringes

Biphasic Inclusions in Amethyst

Biphasic Inclusions

TECTOSILICATES, SILICATES GROUP

Formula  SiO2

  • Crystal system:   Trigonal.
  • Habit:  Hexagonal prism + 2 rhombohedron
  • Hardness (Mohs):   7  
  • Color: Purple
  • Fracture:  Conchoidal
  • Cleavage: None
  • Transparency:  Transparent to translucent
  • Streak: White
  • Lustre:  Vitreous
  • Dispersion: 0,013
  • Density:  2.65 g/cm3
  • Optic nature: Uniaxial positive
  • Refractive index: 1.544 - 1.553
  • Birefringence: 0.009
  • Pleochroism: Weak (purple - violet / pale purple - violet) 
  • Fluorescence: Mostly inert or weak (greenish or bluish)
  • Absorption spectrum:  Not observable

 



Leave a comment

Comments will be approved before showing up.