Click on a letter above to view the list of gems.  

Pyromorphite
Current inventory:  0 gems
 

Chemistry:  Pb₅(PO₄)₃Cl   [Lead Chlorophosphate]

Discovered in 1813;   IMA status: Valid (pre-IMA; Grandfathered).
Named in 1813 from the Greek pyr for "fire" and morfe for "form" because after being melted into a globule a sample will begin to take on a crystalline shape during cooling.

Classification

Mineral Classification:

Phosphates

Strunz 8th Ed. ID:

7/B.39-150

Nickel-Strunz 10th Ed. ID:

8.BN.05

8 : PHOSPHATES, ARSENATES, VANADATES
B : Phosphates, etc., with additional anions, without H₂O
N : With only large cations, (OH, etc.):RO₄ = 0.33:1

Related to:

A member of the Apatite Group, Pyromorphite Subgroup, Mimetite-Pyromorphite Series. It is the phosphate analogue of and is isostructural with Mimetite and Vanadinite. It also forms a series with an unnamed OH-analogue of Pyromorphite.

Crystal Data

Crystallography:

Hexagonal - Dipyramidal

Crystal Habit:

Crystals short to long prismatic, may be acicular [0001], with prominent [1010], [0001], [1011], [2021], hoppered terminations typical, to 8 cm, rarely tabular to equant; radiating to branching groups, tapering to a point. Commonly rounded, globular, reniform, botryoidal.

Twinning:

On [1122], very rare

Physical Properties

Cleavage:

[1011] Imperfect

Fracture:

Irregular, Uneven, Subconchoidal

Tenacity:

Brittle

Hardness (Mohs):

3.5 - 4.0

Density:

7.04 (g/cm³)

Luminescence:

None or may fluoresce yellow to orange under LW and SW UV.

Radioactivity:

Not Radioacitve

Other:

Piezoelectric if Biaxial (may be anomalously Biaxial)

Optical Properties

Color:

Green, Yellow, Brown, Grayish White, Yellowish Red

Transparency:

Transparent to Translucent

Luster:

Adamantine, Resinous

Refractive Index:

2.049 - 2.059  Uniaxial ( - ); may be anomalously Biaxial ( - ), sectored

Birefringence:

0.0100 (very high)

Dispersion:

Very Strong; r > v

Pleochroism:

Weak

Occurances

Geological Setting:

A secondary mineral in the oxidized zone of lead deposits; rarely a volcanic sublimate.

Common Associations:

Anglesite, Cerussite, Galena, Plumbogummite, Smithsonite, Silver, Willemite

Type Locality:

n/a

Year Discovered:

1813

View mineral photos:

Pyromorphite Mineral Photos and Locations

More Information

Mindat.org
Webmineral.com

Pyromorphite is a fairly common mineral but very rarely faceted. It is a secondary lead mineral found in the oxidized zones of lead deposits. Typically found as green to yellow barrel-shaped hexagonal prisms, in clusters or as druses on matrix. Pyromorphite has the same structure as Apatite so crystals of the two will have similar shapes. Pyromorphite also forms a chemical series with Mimetite (Pb5(AsO4)3Cl) and Vanadinite (Pb5(VO4)3Cl). It can be very difficult to tell the difference between green Mimetite or yellow Pyromorphite, but usually Pyromorphite is green and Mimetite is yellow. Vanadinite is usually red.

The main sources of large, bright green, gemmy crystals are Guilin Prefecture, Guangxi Zhuang Autonomous Region, China; Ussel, Corrèze, Limousin, France, Villaviciosa de Córdoba, Sierra Morena, Córdoba, Andalusia, Spain; and Coeur d'Alene District, Shoshone County, Idaho, USA.
 

  
Pyromorphite gems for sale:

We have not photographed the Pyromorphite gems. Please check back soon.