Pringleite – Occurrence, Properties and Distribution

May 15 2013

Topics Covered

Introduction to Pringleite
Properties of Pringleite
How to Identify Pringleite
Global Distribution
Occurrence of Pringleite and Useful Mineral Association
References

Introduction to Pringleite

Pringleite is the triclinic dimorph of Ruitenbergite. It derived its name from Gordon J. Pringle, mineralogist, Geological Survey of Canada, Ottawa, Canada.

Chemical Formula – Ca₉B₂₆O₃₄(OH)₂₄Cl₄13H₂O

Properties of Pringleite

The following are the key properties of Pringleite

Cell Data
- Space Group: P1
- a = 12.746
- b = 13.019
- c = 6.963
- Z = 1
Crystal Data
- Triclinic, pseudomonoclinic
- Point Group: 1
- Subhedral to anhedral crystals up to 2 mm in platy aggregates
- X-ray powder pattern: 7.69 (100), 9.21 (70), 5.74 (60), 4.63 (40), 3.845 (35), 2.199 (30b), 2.058 (30)

Chemical Composition

Elements	Content 1	Content 2
B₂O₃	46.75	45.94
CaO	26.29	25.62
Cl	6.48	7.2
H₂O	[21.94]	22.86
-O = Cl₂	1.46	1.62
Total	[100]	[100]

Optical Properties
- Optical Class: Biaxial ()
- α= 1.537 β= 1.548 γ= 1.570

Estimated Properties

Electron density	Bulk density (electron density)= 2.23 g/cm³ note: Specific gravity of pringleite=2.21 g/cm³
Photoelectric	PE_Pringleite = 2.90 barns/electron U=PE_Pringleite x ρElectron Density= 6.49 barns/cc
Fermion index	Fermion Index = 0.02 Boson Index = 0.98
Radioactivity	Pringleite is not radioactive

How to Identify Pringleite

Pringleite is transparent to translucent. It is colorless to very pale yellow. It is colorless in transmitted light and blue-gray in reflected light.

Global Distribution

Pringleite is distributed from the Potash Corporation of America mine, Penobsquis evaporite deposit, near Sussex, New Brunswick, Canada.

Occurrence of Pringleite and Useful Mineral Association

Pringleite occurs very rarely mostly in an evaporite deposit. Pringleite is associated with Hilgardite-1A, halite, ruitenbergite, sylvite, anhydrite, quartz and clays.