Golden Anglesite Crystals

What a masterpiece creation of mother nature!!! This anglesite is probably one of the very best of its kind ever found! It is large, gemmy, yellow, lustrous and very aesthetic. 
 
Anglesite is a secondary lead mineral, very popular because of its nice gemmy crystals with great luster. It forms by oxidation of galena and other lead ores, often accompanied by other interesting secondary minerals. The formation of cerussite (lead carbonate) often accompanies or follows the formation of anglesite.
 
Unique Golden Anglesite From Morocco
Unique Golden Anglesite From Morocco. Photo Credit: Anton Watzl

Anglesite crystals may consist of impurities of Galena, providing a specimen a gray to black color. In some regions of source, Anglesite occurs as a pseudomorph after Galena, rendering the crystals a false isometric form. Gray and black banding exists in some giant Anglesite specimens that can be observed when a specimen is either sliced or polished.

The crystal habit of anglesite is frequently tabular or thick tabular, often with pointed terminations. The main crystal faces are usually striated. It also forms as nodular, stalactitic, banded, crusty, reniform or granular masses.

Anglesite is named for its type locality of Anglesey, an island at the northern tip of the United Kingdom. It is a secondary mineral, typically formed in the oxidation zone of galena (lead sulfide) ores.
 

There are only three primary uses of anglesite – as a lead ore, as an occasional gemstone, and as a mineral specimen. 
 
Golden Anglesite Crystals
Unique Golden Anglesite From Morocco.
Photo Credit: Anton Watzl



Anglesite |
#Geology

Formula: PbSO4
Color is usually colorless, white and yellow; also pale gray, blue and green.
Luster is adamantine.
Transparency crystals are transparent to translucent.
Crystal System is orthorhombic; 2/m 2/m 2/m
Crystal Habits include the bladed or tabular crystals that are dominated by two large pinacoid faces top and bottom and small prism faces forming a jutting angle on every side. There are many variations of these faces and complex forms can occur. If the pinacoid faces become diminished or are absent, the resulting prismatic crystal has a rhombic cross section.. Anglesite typically forms a flattened blade that juts out from a host rock and with what appears to be a steep dome termination but is actually two faces of another rhombic prism. Also forms crusts and is granular and massive.
Cleavage is perfect in one direction, less so in two other directions.
Fracture is conchoidal.
Hardness is 2.5 - 3.
Specific Gravity is approximately 6.3+ (very heavy for translucent minerals)
Streak is white.
Associated Minerals are galena, cerussite, barite and limonite.
Other Characteristics: Index of refraction is 1.88+ (very high), some specimens fluoresce yellow under UV light.
Notable Occurances include Tsumeb, Nambia; Australia; England, Mexico and Toussit, Morocco.
Best Field Indicators are crystal habit, density, high luster and color.

The specimen in the photo is From: Touissit, Oujda-Angad Prov., Oriental Region, Morocco


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