Roweite - Occurrence, Properties, and Distribution

May 15 2013

Topics Covered

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

Introduction to Roweite

Chemical Formula – Ca₂Mn⁺⁺₂B₄O₇(OH)₆

Roweite is an orthorhombic-dipyramidal light brown mineral containing oxygen, manganese, hydrogen, calcium and boron. It was first discovered in 1937 from Franklin, Sussex Co., New Jersey, USA. The mineral was named to honor George Rowe, Mine Captain at Franklin, New Jersey, USA and a mineral collector.

Properties of Roweite

The following are the key properties of Roweite:

Cell Data
- Space Group: Pbam
- a = 8.27–8.289
- b = 13.25–13.357
- c = 9.01–9.057
- Z = 4
Crystal Data
- Orthorhombic
- Point Group: 2/m 2/m 2/m
- Lathlike crystals, to 5 mm, flattened on {100}, elongated and striated along [010], showing {001}, {100}, {021}, {201}, {401}, with rough {010}, {021} as terminations; compact massive
- X-ray Powder Pattern: 3.974 (100), 2.600 (72), 2.184 (49), 2.128 (37), 2.264 (32), 1.708 (32), 1.641 (29)

Chemical Composition

Elements	Content 1	Content 2	Content 3
B₂O₃	32.40	30.2	34.15
MnO	28.30	-	17.87
CaO	25.40	-	23.96
H₂O	8.51	11.9	13.40
ZnO	3.13	-	-
MgO	1.66	-	7.59
SiO₂	-	-	1.37
Fe₂O₃	-	-	0.13
FeO		-	1.20
insol.	0.84	-	-
Total	100.24	-	99.67

Optical Properties
- Optical Class: Biaxial (–)
- Pleochroism: Moderate
- X = very pale brown to colorless
- Y = pale amber
- Z = yellowish brown
- Orientation: X = c; Y = b; Z = a
- Dispersion: r < v, strong
- Absorption: X > Y > Z
- α = 1.631–1.648
- β = 1.640–1.660
- γ = 1.641–1.663
- 2V(meas.) = 15°–28°

Estimated Properties

Electron density	Bulk density (electron density)=2.89 g/cm³ note: Specific gravity of Roweite =2.94 g/cm³
Photoelectric	PE_Roweite = 8.54 barns/electron U= PE_Roweite x ρElectron density= 24.65 barns/cm³
Fermion index	Fermion index = 0.01 Boson index = 0.99
Radioactivity	Roweite is not radioactive

How to Identify Roweite

Roweite is a transparent, light brown mineral having a vitreous luster, light brown streak, and indistinct cleavage. It has brittle fractures that produce small, conchoidal fragments. The relative hardness of roweite is 5, and its density is 2.94 g/cm³.

Global Distribution

Roweite is distributed in the following places:

Franklin, Sussex Co., New Jersey, USA
Solongo boron deposit, Buryatia, Russia.

Occurrence of Roweite and Useful Mineral Association

Roweite occurs in hydrothermal veins in a metamorphosed stratiform zinc orebody. Zincite, willemite, franklinite, calcite and clinochrysotile are closely associated with roweite.