SUGILITE

Introduction:  Sugilite is a mineral species.  Pictured above is sugilite on matrix and a faceted tablet weighing 3.93 ct, displaying the classic grape jelly color.

Colors:  semitransparent to opaque, red-purple to blue-purple.  It is sometimes sold under the trade names Royal Azel or Royal Lavulite.

Clarity:  There is no clarity type classification.  Semitransparent material is sometimes faceted and should be eye clean.  Cabochons, carvings and beads should be free from cracks.

Stone Sizes:  Large pieces have been available.  

Localities:
-Wessels Mine, Kuruman district, near Hotazel, South Africa:  Cuttable material was first found in 1975.  Around 1980, a huge mass of pehaps 10-12 tons of sugilite was discovered at a depth of 3200 feet.  Only half of the material had the grape jelly color associated with the gem and of this, only a tiny percentage (0.1%) was translucent.

Treatments:
-None

Gemology:
-Refractive Index:  1.607-1.610 (+0.001, -0.002).  Quartz impurities may alter the RI.

-Birefringence:  usually not detectable

-Optic Character:  Doubly refractive, uniaxial negative; AGG

-Specific Gravity:  2.74 (+/- 0.05)

-Hardness:  5.5 to 6.5

-Toughness:  good

-Chemical Composition:  (K,Na)(Na,Fe)2(Li2Fe)Si12O30

-Cause of Color:  Manganese, iron

-Fluorescence:  inert

-Absorption Spectra:  550 nm band, 411, 419, 437 and 445 nm lines

-Cleavgae:  None

-Phenomena:  None

Name:  Sugilite is named after Professor Ken-ichi Sugi, the Japanese petrologist who first discovered the material in 1944.

Dates:  None

Care:  Both the ultrasonic and steam cleaner are risky.  Warm, soapy water is safe.

To see available sugilites, click here.