Endlichite can be an variety that is arsenic-rich of. It forms a solution that is complete between Vanadinite and Mimetite, with increasing quantities of Arsenic replacing Vanadium. Endlichite is just a rare mineral that is secondary through the oxidation of primary lead minerals such as Galena. It precipitates from aqueous solutions in veins and solution cavities, along along with other lead that is secondary.

There are just four locations for finding Endlichite: Erupción Mine (Ahumada Mine; Erupción-Ahumada Mine), Los Lamentos Mts (Sierra de Los Lamentos), Mun. de Ahumada, Chihuahua, Mexico; Ojuela Mine, Mapimí, Mun. de Mapimí, Durango, Mexico; Midelt, Khénifra Province, Meknès-Tafilalet Region, Morocco; Chalk Mountain Mine, Chalk Mountain District, Churchill Co., Nevada,Usa.

chemical formula: Pb5([V,As]O4)3Cl
Crystallography: Hexagonal – Dipyramidal
Crystal Habit: Well developed hexagonal prisms [0001] with smooth faces and sharp edges; commonly cavernous, also acicular, hairlike, fibrous, rounded, globular, skeletalized. Crystals may exhibit concentric zones of varying composition.
Twinning: None


Cleavage: None
Fracture: Irregular/Uneven, Conchoidal
Tenacity: Brittle
Hardness (Mohs): 2.5 – 3.0
Density: 6.88 (g/cm3); Density decreases with the substitution of Ca for Pb; repaorted values range between ~6.5 to 7.1.
Luminescence: None
Radioactivity: Not Radioactive
Health Warning: CAUTION: Contains Arsenic – always wash hands after handling. Avoid inhaling dust when handling or breaking. Never lick or ingest.
Other: Readily soluble in HNO3 to a yellow solution; soluble in HCl to a green solution with the deposition of lead chloride.


Color: Orange, Orangish Brown, Brown
Transparency: Translucent to Opaque
Luster: Adamantine to Sub-Adamantine, Resinous
Refractive Index: 2.350 – 2.416  Uniaxial ( – )
Birefringence: 0.0660
Dispersion: Strong
Pleochroism: Weak; Visible in tinted material in transmitted light; Dichroism: e = light, w = darker