Mozgovaite - Occurrence, Properties, and Distribution

May 16 2013

Topics Covered

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

Introduction to Mozgovaite

Chemical Formula – PbBi₄(S,Se)₇

Mozgovaite is an orthorhombic-dipyramidal silver gray mineral containing sulfur, selenium, lead and bismuth. The mineral was first found in La Fossa crater, Isle Vulcano, Aeolian Islands, Italy in 1998. It was named after the Russian mineralogist Nadezhda N. Mozgova.

Properties of Mozgovaite

The following are the key properties of Mozgovaite:

Cell Data
- Space Group: Bbmm (by analogy to synthetic PbBi₄S₇)
- a = 13.18(6)
- b = 37.4(2)
- c = 4.05(3)
- Z = 6
Crystal Data
- Orthorhombic
- Point Group: 2/m 2/m 2/m
- Acicular crystals, to 600 µm, in sprays
- X-ray Powder Pattern: 3.80 (10), 2.95 (4B), 2.34 (4B), 3.58 (3), 3.30 (3), 3.40 (2), 3.11 (2).

Chemical Composition

Elements	Content 1	Content 2
Bi	64.79	65.94
S	16.91	17.71
Pb	13.90	16.35
Cd	0.26	-
As	0.05	-
Fe	0.02	-
Cu	0.01	-
Total	97.57	100.00

Optical Properties
- Optical Class: Biaxial
- Anisotropism: Strong, without color effects
- Bireflectance: Very weak.

Estimated Properties

Electron density	Bulk density (electron density)=5.29 g/cm³ note: Specific gravity of Mozgovaite =6.38 g/cm³
Photoelectric	PE_Mozgovaite = 1570.05 barns/electron U= PE_Mozgovaite x ρElectron density= 8307.59 barns/cm³
Fermion index	Fermion index = 0.03 Boson index = 0.97
Radioactivity	Mozgovaite is not radioactive

How to Identify Mozgovaite

Mozgovaite is a silver gray mineral having a metallic luster, gray streak and opaque nature. The mineral can be formed as prismatic crystals, and it has a hardness range of 2.5 to 3.5.

Global Distribution

Mozgovaite is widely distributed in the Fossa crater, Vulcano, Lipari Islands, Italy.

Occurrence of Mozgovaite and Useful Mineral Association

Mozgovaite occurs as a sublimate in a volcanic fumarole. It is closely associated with minerals such as galenobismutite, lillianite, cannizzarite and bismuthinite.