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Chemical Formula | PbSO4 | ||
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Composition | Lead sulfate | ||
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Color | Colorless, white, yellow, brown, green, orange, reddish, gray to black from Galena impurities; also banded gray and black | ||
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Streak | White, but light gray if it has impurities from Galena | ||
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Hardness | 2½ - 3 | ||
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Crystal Forms and Aggregates |
(Orthorhombic) Most commonly occurs in tabular or prismatic crystals, sometimes elongated. Crystals may also be bipyramidal, and are frequently striated. Also occurs grainy, crusty, massive, reniform, and stalactitic. Anglesite is unique for it never forms pseudohexagonal trillings as other members of its group do. | ||
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Transparency | Transparent to translucent in thin splinters | ||
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Specific Gravity | 6.4 | ||
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Luster | Adamantine, submetallic | ||
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Cleavage | 2,1 - basal ; 3,1 - prismatic | ||
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Fracture | Conchoidal | ||
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Tenacity | Brittle | ||
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Other ID Marks | Commonly fluoresces light yellow in shortwave ultraviolet light | ||
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In Group | Sulfates ; Anhydrous sulfates | ||
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All About | Anglesite is a secondary lead mineral that always forms through the alteration of lead sulfides, primarily Galena. Anglesite crystals may contain impurities of Galena, giving a specimen a gray to
black color. In some localities, Anglesite forms pseudomorphs after Galena, giving the crystals
a false isometric form. Gray and black bands are present in some massive Anglesite specimens, which can be seen when polished or cut open. Such specimens frequently contain unaltered Galena in the center, which did not change over to Anglesite when the outer layers altered. |
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Uses | Anglesite is an ore of lead, although crystals are preserved when possible, due to their high value to collectors. | ||
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Striking Features | Heaviness, adamantine luster, mineral associations, and untwinned crystals | ||
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Popularity (1-4) | 2 | ||
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Prevalence (1-3) | 3 | ||
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Demand (1-3) | 1 | ||
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Distinguishing Similar Minerals |
Celestine - lacks adamantine luster, lighter in weight (3.9 - 4.0) Barite - lacks adamantine luster Cerussite - effervesces in hydrochloric acid, crystals frequently twinned Phosgenite - very hard to distinguish from Anglesite, but occurs in different crystals, and is sectile and nonbrittle. |
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Commonly Occurs With |
Galena, Cerussite, Phosgenite, Smithsonite, Hemimorphite, Sphalerite, Azurite, Malachite, Sulfur, Pyromorphite | ||
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Noteworthy Localities |
Some of the largest Anglesite crystals were
found in Tsumeb, Namibia, and excellent specimens came
from Mibladen and Touissit, Morocco. It has also been
found in the Black Forest of Germany; New Caledonia;
Ciudad Real, Spain; Caldbeck Fells, Cumbria, England; and
on the island of Anglesey in Wales, which is the original
occurrence of this mineral and the cause of its name.
Lustrous crystals have been found at Montevecchio and
Monteponi on the island of Sardinia, Italy. In New South
Wales, Australia, it is found associated with Cerussite. In Mexico, yellowish crystals embedded in Sulfur were found in Los Lamentos, Chihuahua. In the U.S., white crystals associated with Pyromorphite have come from the Wheatley Mines in Phoenixville, Chester Co., Pennsylvania. The area of Joplin, Ottawa Co., Missouri has produced isometric pseudomorphs of Anglesite over Galena, as well as "banded" Anglesite. Specimens have also been found in Bisbee, Cochise Co., Arizona; the Tintic District, Juab Co., Utah; the Blue Bell mine, San Bernardino Co., California; the Yellow Pine Mine, Clarke Co., Nevada; the Coeur d'Alene District and the Hypotheek Mine, Shoshone Co., Idaho. |
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Picture Icon Links |
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Picture Links | 1. Colorless Anglesite crystal |
