Augelite
Current inventory:  1 gems
 

  
Augelite is named from the Greek word auge, meaning shine or luster, in allusion to the pearly luster on its cleavage surfaces.

Discovered in 1868;   IMA status: Valid (pre-IMA; Grandfathered)

Chemistry

Chemical Formula:

Al₂(PO₄)(OH)₃

Aluminum Phosphate Hydroxide

Molecular Weight:

199.96 gm

Composition:

Aluminum

26.99 %

Al

50.99 %

Al₂O₃

Phosphorus

15.49 %

P

35.49 %

P₂O₅

Hydrogen

1.51 %

H

13.51 %

H₂O

Oxygen

56.01 %

O

100.00 %

100.00 %

= TOTAL OXIDE

Classification

Mineral Classification:

Phosphates

Strunz 8th Ed. ID:

7/B.12-20

Nickel-Strunz 10th Ed. ID:

8.BE.05

8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H₂O
E : With only medium-sized cations, (OH, etc.):RO₄ > 2:1

Related to:

n/a

Varieties:

None

Synonyms:

Amfihalite, Amfithalite, Amphitalite, Amphithalite

Crystal Data

Crystallography:

Monoclinic - Prismatic

Crystal Habit:

As thick tabular crystals, to 13 cm, may be prismatic, even acicular, showing many forms, striated; may be massive.

Twinning:

None

Physical Properties

Cleavage:

Perfect on {110}, Good on {201}, Imperfect on {001} and {101}

Fracture:

Irregular/Uneven

Tenacity:

Brittle

Moh's Hardness:

4.5 - 5.0

Density:

2.696 (g/cm³)

Luminescence:

None

Radioactivity:

Not Radioactive

Other:

Slowly soluble in hot concentrated HCl.

Optical Properties

Color:

Colorless, Yellow, Yellow Green, Greenish, White, light Blue, light Pink

Transparency:

Transparent to Translucent

Luster:

Vitreous, Pearly on perfect cleavage {110}

Refractive Index:

1.5736 - 1.5877  Biaxial ( + )

Birefringence:

0.0141

Dispersion:

None

Pleochroism:

None

Occurances

Geological Setting:

Formed by hydrogen metamorphism of phosphate-bearing rocks in peraluminous sediments; in some high-temperature hydrothermal ore deposits.

Common Associations:

Attakolite, Berlinite, Lazulite

Common Impurities:

None

Type Locality:

Västanå Iron Mine (Westanå Mine), Näsum, Bromölla, Skåne, Sweden

Year Discovered:

1868

View mineral photos:

Augelite Mineral Photos and Locations

More Information

Mindat.org
Webmineral.com

Augelite is an extremely rare collector's gem. It is a rare Phosphate mineral that is relatively soft (4.5 - 5.0 Mohs hardness). Until a find at White Mountain, Mono County, California, Augelite was only known as very tiny crystals or masses. This source is now depleted. The only current sources for gem quality crystals are Rapid Creek, Dawson Mining District, Yukon Territory, Canada; Ancash Department, Peru; Groton, Grafton County, New Hampshire, USA. Even these sources only produce very small crystals, most of which are highly included or opaque.

Augelite is found at the Västanå mine, near Näsum, Skåne, and at Hålsjöberg, Värmland, Sweden. At Mbale, Uganda. In the Buranga pegmatite, near Gatumba, Rwanda. In the USA, large crystals from the Champion mine, White Mountains, Mono County, California; in New Hampshire, at the Palermo #1 mine, near North Groton, Grafton County, and the G.E. Smith mine, Newport, Sullivan County; in the Hugo and Ingersoll mines, near Keystone, Pennington County, South Dakota; in the White Picacho district, Maricopa and Yavapai Counties., Arizona. From the Big Fish River–Rapid Creek area, Yukon Territory, Canada. In Bolivia, from the Socavón mine, San José, and Itos mines, Oruro; at Llallagua, Machacamarca, Tatasi, and Portugalete, Potosí. From Mt. Perry, 75 km southwest of Bundaberg, Queensland, Australia. Additional localities are known.
 

  
Augelite gems for sale: