The Mineral VANADINITE
- Chemistry: Pb5(VO4)3Cl , Lead Chlorovanadate
- Class: Phosphates
- Group: Apatite
- Uses: as a minor ore of lead and mineral specimens
Vanadinite shares the same structure with Apatite and the two share similar crystal shapes at times.
Vanadinite is part of a chemical series with two other minerals;
This series is a little different than most chemical series which involve substitution of cations such as calcium for magnesium.
Instead, this series substitutes its basic chemical units the anion groups; phosphate (PO4
), arsenate (AsO4
) and vanadate (VO4
Vanadinite is usually red which the other members of this series and apatite group usually are not.
Vanadinite's classic crystal habit is short hexagonal prisms terminated by a pinacoid, or flat basal face.
These crystals are wider than they are long and are more blade-like than the barrel shaped crystals so common to the Apatite Group minerals.
The high luster and deep red color give vanadinite a nice appeal to mineral collectors.
- Color is typically bright red to orange, less commonly gray or brown.
- Luster is vitreous to adamantine.
- Transparency crystals are transparent to translucent.
- Crystal System is hexagonal; 6/m
- Crystal Habit is typically the hexagonal prism with pinacoid as a termination.
Rare crystals can have the hexagonal pyramid as a termination.
Can also be found as rounded masses and crusts.
- Cleavage is none.
- Fracture is conchoidal.
- Hardness is 3.
- Specific Gravity is approximately 6.6+ (very heavy for translucent minerals)
- Streak is yellowish white.
- Associated Minerals are wulfenite, limonite, barite, galena and secondary lead deposit minerals.
- Other Characteristics: index of refraction is 2.39 (typically high for lead minerals) and crystal terminations can be hollowed out or pitted but not as often as pyromorphite or mimetite.
- Notable Occurances include Arizona, USA; Mexico; Tsumeb, Nambia; Zambia; and South Africa.
- Best Field Indicators are color, crystal habit, high luster and density.