Click on a letter above to view the list of gems.  

Hanksite
Current inventory:  0 gems
 

Chemistry:  KNa₂₂(SO₄)₉(CO₃)₂Cl

Discovered in 1885;   IMA status: Valid (pre-IMA; Grandfathered).
Hanksite is named in honor of Henry Garber Hanks (1826–1907), for his service as first State Mineralogist of California, USA.

Classification

Mineral Classification:

Sulfates

Strunz 8th Ed. ID:

6/B.14-30

Nickel-Strunz 10th Ed. ID:

7.BD.30

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
B : Sulfates (selenates, etc.) with additional anions, without H₂O
D : With only large cations

Related to:

Hectorfloresite - Hanksite Series

Crystal Data

Crystallography:

Hexagonal - Dipyramidal

Crystal Habit:

As short prismatic to tabular hexagonal crystals, to 20 cm, striated.

Twinning:

None

Physical Properties

Cleavage:

[0001] Good

Fracture:

Conchoidal, Irregular/Uneven

Tenacity:

Brittle

Hardness (Mohs):

3.0 - 3.5

Density:

2.562 (g/cm³)

Luminescence:

Pale Yellow under LW UV

Radioactivity:

Barely Detectable; GRapi = 35.47 (Gamma Ray American Petroleum Institute Units)

Other:

Readily soluble in water. Saline taste.

Optical Properties

Color:

Colorless to pale Yellow or almost Black; may be Grayish Green due to clay inclusions

Transparency:

Transparent, Translucent

Luster:

Vitreous, Dull

Refractive Index:

1.461 - 1.481  Uniaxial ( - )

Birefringence:

0.0200

Dispersion:

n/a

Pleochroism:

None

Occurances

Geological Setting:

In lacustrine evaporite deposits.

Common Associations:

Aphthitalite, Borax, Halite, Trona (Searles Lake, California, USA).

Type Locality:

Searles Lake, San Bernardino Co., California, USA

Year Discovered:

1885

View mineral photos:

Hanksite Mineral Photos and Locations

More Information

Mindat.org
Webmineral.com

Hanksite is somewhat common as a mineral but rarely faceted as a gem. It is difficult to facet because it is readily soluble in water so another liquid such as alcohol must be used. Hanksite is an unusual mineral because it is one of very few minerals that contain both carbonate and sulfate ion groups. Some mineral references place it in the carbonate while others put it with the sulfates. Hanksite forms very nice crystals in evaporite deposits in arid environments. Hanksite crystals can be large and well formed, but are very simple.

There are very few loactions for Hanksite. The best known is Searles Lake, San Bernardino County, California, USA.
 

  
Hanksite gems for sale:

We have not photographed our Hanksite gems. Please check back soon.