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- Chemistry: PbCO3, Lead Carbonate
- Class: Carbonate
- Group: Aragonite
- Uses: As an ore of lead and as mineral specimens.
Specimens
Crystallographers can appreciate cerussite's sparkle and density; but it is cerussite's wonderfully twinned crystals that get them excited! This mineral can form some geometrically intricate structures and spoked star shapes that simply are amazing. Cerussite belongs to the Aragonite Group of minerals. A group that as a whole is well known for twinning with commonly twinned members such as aragonite, witherite and strontianite Twinning is most definitely common in cerussite and besides the intricate structures mentioned already, singular twins are also interesting. There are three basic types of twinning in cerussite: Elbow or chevron shaped twins, cyclic twins and last but not least, reticulated twins. The elbow or chevron shaped twins are the most common and are generally seen on most specimens. The cyclic twins often form star shapes with six "spokes" extending from the star. Very beautiful! The reticulated twins are classics and form complex interconnected beams of crystals. So intricate are these specimens they appear to have been constructed. They truly are an awesome mineralogical wonder. Cerussite twins are a must for collectors who are fond of twinned crystals.
Cerussite is found in the oxidation zone of lead deposits usually associated with galena. Some specimens show cerussite crusts around a galena core as the oxidation was "caught in the act" so to speak. Cerussite can make nice associations with galena and another lead mineral anglesite, a yellow colored, lead sulfate. Cerussite is simply a classic!
When gold was discovered near Leadville, Colorado (before it was a town), panning for alluvial gold was difficult because of the dense brown sand in the streams. This sand was later found to be primarily cerussite, and contained significant amounts of silver. This started a silver mining boom, and ultimately lead to huge production of silver, lead, and zinc.
The name "cerussite" is from the Latin word cerussa, meaning white lead. It is also commonly misspelled, often with only one "s", or with two r's, or both: cerrussite, cerusite, and cerrusite are all seen instead of the correct spelling, cerussite. It has also been known as Horn Silver and lead spar.
PHYSICAL CHARACTERISTICS:
- Color is usually colorless or white, also gray, yellow, and even blue-green.
- Luster is adamantine to almost submetallic and sometimes greasy.
- Transparency Crystals are transparent to translucent.
- Crystal System is orthorhombic; 2/m 2/m 2/m.
- Crystal Habits twinning is common and expected (see above), single crystals can be prismatic with blunted pyramidal terminations. Some specimens show acicular white crystals. Also, reniform, earthy, and crusty varieties are found.
- Cleavage is not as good as other carbonates, but still considered good in one direction.
- Fracture is conchoidal and brittle.
- Hardness is 3-3.5.
- Specific Gravity is 6.5+ (very dense for a generally transparent mineral).
- Streak is white or colorless.
- Other Characteristics: Refractive index of 2.07 (very high) and prismatic crystals are striated lengthwise.
- Associated Minerals are barite, calcite, anglesite, and other secondary minerals and especially galena.
- Notable Occurrences include Tsumeb, Nambia; Congo; Morocco; Australia; Germany, Leadville, Colorado and Arizona, USA.
- Best Field Indicators are its crystal habit (especially twins), heaviness, high refraction and luster.
 Amethyst Galleries' Mineral Gallery MINERALS |
CERUSSITE specimen cer-1
$ 22.50
$ 22.50
Dims: 2-3/4" x 1-3/4" x 1-1/2"
Wt: 7.1 oz
Toussit, Morocco
This little Moroccan Cerussite specimen has an extraordinary trait to it. The cluster is composed of several creamy-white tabular crystals, ranging in size from 3/4 inch to 2-1/4 inch in length, on a Galena base. One of the crystals is damaged; the point is broken off, revealing a little secret. The crystals' off-white color is due to a coating that surrounds a clear and colorless center. I'm guessing that the crystals are pure Cerussite, and the layering was caused by a change in the growing conditions. I've not seen a Cerussite specimen such as this one before.
cer-1 ($ 22.50)
Toussit, Morocco
CERUSSITE specimen cer-3
$ 36.00
$ 36.00
Dims: 1-1/4" x 1-1/4" x 3/4"
Wt: 1.55 oz
Tsumeb, Namibia
Cerussite twins are not an uncommon occurrence-- this specimen is no exception. As a matter of fact, there is evidence of multiple twinning of the crystals-- though incomplete, one can make out the form of a trilling, a twinning variation in which a crystal is twinned 3 times at 60- or 120-degree angles, so that there seem to be either 3 or 6 crystals radiating from a central point along one plane. There are a few "legs" of the trilling missing and quite a bit of damage otherwise, but the Cerussite is quite transparent, has clean faces where applicable, and a pale brown color. There is a black matrix material that has the subadamantine luster of a lead mineral like Cerussite, but I cannot identify it-- it may even be a small spot of plattnerite, who knows?
cer-3 ($ 36.00)
Tsumeb, Namibia
CERUSSITE specimen cer-5$ 115.00
Dims: 2.0" x 1.3" x 1.0"(5.1 x 3.3 x 2.5 cm)
Wt: 2.25 oz.(63.9 g) w/ base
Broken Hill Mine, Kabwe, Zambia
This Cerussite specimen is small but very impressive; it consists of a cluster of many crystals that are intergrown and packed together tightly enough to become two singular, flat, crystalline "units" that intersect each other at a 60-degree angle. Like the units that they make up, the orthorombic prismatic crystals also intersect each other at 60-degree angles, creating complex triangular patterns on the flat faces of the units. One side of each unit has the pale gray-beige coloration, adamantine luster, and translucence/transparence of Cerussite, and is more densely packed than the other side of each face, which has a dark gray color, duller luster, and is opaque and has loosely arranged crystals. Some of these crystals grow outward from the units, so one can clearly see their form, but most are completely assimilated. I don't know what causes the dark gray color, but there is very little of it,
cer-5 ($115.00)Broken Hill Mine, Kabwe, Zambia
CERUSSITE specimen cer-10
$ 80.00
$ 80.00
Dims: 1.4 x 1.1 x 0.7" (3.6 x 2.8 x 1.8 cm)
Wt: 1.34 oz. (38.1 g)
Tsumeb Mine, Namibia
Though it is difficult to count them all, there are at least 15 orthorhombic prismatic Cerussite crystals gathered on the galena base of this specimen. These crystals achieve lengths of up to 0.6" (1.5 cm) and are in excellent condition, as they show damage only around the edges of the cluster. All have excellent form, with well-defined edges and heavily striated but clean faces that possess a bright adamantine luster. The largest crystal appears to be twinned (see the close-up image). All of them have a pale brown coloration and are transparent and quite clear, containing only a few internal fractures and some subtle zonation of color. Their galena base is dull and weathered, and lacks any crystalline structure.
cer-10 ($ 80.00)
Tsumeb Mine, Namibia
CERUSSITE specimen cer-11
$ 50.00
$ 50.00
Dims: 2.0 x 1.9 x 1.4" (5.1 x 4.8 x 3.6 cm)
Wt: 2.8 oz. (79.2 g)
Mibladen, Morocco
This large thumbnail specimen consists if two clusters and a few loose crystals of Cerussite that rest on a base of barite blades. One of the clusters is quite large, with dimensions of 1.1 x 1.0 x 0.8" (2.8 x 2.5 x 2.0 cm). A single crystal makes up most of the cluster, and its dimensions are only slightly smaller. The smaller cluster has dimensions of 0.9 x 0.4 x 0.4" (2.3 x 1.0 x 1.0 cm); the crystals that make it up are all aligned in a similar direction. The crystals are generally in excellent condition, showing almost no damage. They all have good orthorhombic prismatic form, with well-defined edges and clean faces that show an almost adamantine luster. All have a pale-brown coloration and are translucent. The barite base on which they rest is conside
cer-11 ($ 50.00)
Mibladen, Morocco
CERUSSITE specimen cer-12
$ 68.00
$ 68.00
Dims: 2.2 x 0.8 x 0.8" (5.6 x 2.0 x 2.0 cm)
Wt: 1.51 oz. (42.8 g)
Toussit, Morocco
A parallel association of several prismatic Cerussite crystals makes up this thumbnail specimen. The association appears to be in excellent condition, as none of the crystals therein show any human-induced damage. All have rather warped orthorhombic forms due to their heavy intergrowth, but the many edges are well-defined, and their faces are clean and possess the standard adamantine luster. There is even one small but complete termination present. Its very pale brown coloration is standard for this mineral, and though the association is generally cloudy and translucent, there are noticeable patches of transparence at its "terminations". A tiny patch of broken galena on its base makes up the extent of the host rock that is present.
cer-12 ($ 68.00)
Toussit, Morocco
CERUSSITE specimen cer-13
$ 36.00
$ 36.00
Dims: 2.7 x 2.4 x 1.2" (6.9 x 6.1 x 3.0 cm)
Wt: 5.29 oz. (150.1 g)
Mibladen, Morocco
Several dozen intergrown Cerussite crystals make up a crust that coats the limestone host rock of this specimen. The crystals are rather small, not exceeding 0.4" (1.0 cm) along any axis, but are generally in excellent condition, showing very little damage. Intergrowth slightly warps their orthorhombic prismatic form, but it is still basically good, with moderately well-defined edges and often striated but clean faces that possess an adamantine luster. Their color is a pale creamy-brown, and all are transparent and moderately to dimly clear due to various inclusions and the odd internal fracture. Accompanying the Cerussites on their thin limestone crust is a cluster of well-formed barite blades that have a pink-orange color and are translucent. The cluster is wedged in a small hollow, and so is well-protected and in very good condition.
cer-13 ($ 36.00)
Mibladen, Morocco
CERUSSITE specimen cer-14
$ 94.00
$ 94.00
Dims: 2.0 x 1.5 x 1.2" (5.1 x 3.8 x 3.0 cm)
Wt: 1.70 oz. (48.4 g)
Tsumeb, Namibia
Four pseudohexagonal Cerussite crystals rest on the thin, green base of this specimen. The two largest crystals reach lengths of approximately 1" (2.5 cm) and are damaged and not complete, but the others are intact and very good condition. Their orthorhombic form is good, with well-defined edges and heavily-striated but clean faces that possess an adamantine luster. All have a very pale beige coloration and are transparent and moderately to dimly clear, containing many internal fractures and a few cloudy inclusions. They rest on a crust that is made up of many small, intergrown dolomite crystals. These crystals do not exceed 0.2" (5 mm) in length and are in good condition. The crust is heavily coated with microcrystalline or massive green duftite (a lead copper arsenate hydroxide) on one side.
cer-14 ($ 94.00)
Tsumeb, Namibia
CERUSSITE specimen cer-15
$ 60.00
$ 60.00
Dims: 2/1 x 2.0 x 1.9" (5.3 x 5.1 x 4.8 cm)
Wt: 3.01 oz. (85.4 g)
Grand Reef Mine, Klondyke, Graham County, Arizona, U.S.A.
Several small Cerussite prisms rest in a hollow in the host rock of this large thumbnail specimen. These crystals generally do not exceed 0.3" (8 mm) along any axis, but there is a parallel association of several heavily intergrown crystals that exceeds those dimensions. Only two crystals, located at the edge of the hollow, are damaged, and both of these are incomplete. The others are intact and in excellent condition. Their orthorhombic form is excellent, as all have well-defined edges and clean faces that possess the standard adamantine luster. They have a pale beige coloration and are transparent and moderately to dimly clear, as most contain cloudy inclusions. They are accompanied by a druse of tiny amethyst crystals that lines the hollow. The surrounding host rock is rust-stained and appears to consist of both crystalline and microcrystalline quartz.
cer-15 ($ 60.00)
Grand Reef Mine, Klondyke, Graham County, Arizona, U.S.A.
CERUSSITE specimen cer-16
$ 85.00
$ 85.00
Dims: 2.9 x 2.0 x 1.8" (7.4 x 5.1 x 4.6 cm)
Wt: 5.10 oz. (144.5 g)
Grand Reef Mine, Klondyke, Graham County, Arizona, U.S.A.
This small hand specimen consists of several intergrown Cerussite crystals that rest in a hollow in a pale brown quartzite host rock. The largest of these crystals are twinned and measure approximately 0.8" (2.0 cm). They are likely the only intact and complete crystals on the piece, as the others are more exposed and all appear to be broken to a degree. Their orthorhombic prismatic form is very good, though restricted growing space has not allowed them to terminate. All edges are well-defined and all faces are smooth, however, and possess the standard adamantine luster. Their pale, creamy color and milky translucence are likewise common for the species. The hollow in which the crystals rest is lined with a druse of tiny quartz crystals that have a faint violet hint. A very faint blue coloration on some of them makes me think that a small amount of copper is also present in the surrounding host.
cer-16 ($ 85.00)
Grand Reef Mine, Klondyke, Graham County, Arizona, U.S.A.
CERUSSITE specimen cer-17$ 375.00
Dims: 2.3 x 2.2 x 0.9" (5.8 x 5.6 x 2.3 cm)
Wt: 3.32 oz. (94.0 g)
Toussit Mine, near Oudja, Morocco
This hand specimen consists of 2 Cerussite crystals that grew apart from each other off of a twinning plane. The larger of the crystals measures 2.5" (6.4 cm) in length, whereas the smaller measures 1.7" (4.3 cm). Both are in very good condition, though the larger crystal has 3 small, conchoidal chips. Both have a rather unusual orthorhombic form that is not quite bladed, but not quite prismatic- they show many growth-related striations and faces. Theyhave odd, thin terminations; the larger crystal has an uneven termination that likely did not form completely due to lack of space, whereas the smaller termination is more complete and ends on a flat edge. Both crystals have a pale, creamy-brown color on its outer edges that fades to a slightly darker brown color at their centers. They are translucent and cloudy and show an amazing, pearly shimmer beneath their adamantine luster. There is no host rock present, and a few edges and crevices contain tiny amounts of a dull, pale brown material. This is one of the finest Cerussite pieces that I have seen outside of a museum.
cer-17 ($375.00)Toussit Mine, near Oudja, Morocco
CERUSSITE specimen cer-18
$ 25.00
$ 25.00
Dims: 3.2 x 2.8 x 1.5" (8.1 x 7.0 x 3.7 cm)
Wt: 6.7 oz. (189 g)
Toussit Mine, near Oudja, Morocco
At least 6 small Cerussites rest on the limestone base of this hand specimen. These crystals are in excellent condition and reach maximum dimensions of 0.6 x 0.5 x 0.4" (1.4 x 1.2 x 0.9 cm). The smaller crystals have the standard orthorhombic bladed form, but the largest one appears to be hexagonal due to cyclic twinning. Their color is a dull yellow-brown, their luster is not quite adamantine, and all are dimly transparent. One or two barite blades and several clusters of near-microscopic galenas rest among them.
cer-18 ($ 25.00)
Toussit Mine, near Oudja, Morocco
CERUSSITE specimen cer-19
$ 70.00
$ 70.00
Dims: 2.95x2.64x1.46" (7.9x6.7x3.7cm)
Wt: 15.5oz. (439g)
Masif de belle donne, Isere, France
This heavy hand specimen has over 100 cerussite crystals are scattered over the surface of black crystalline mass of axinite (per the documentation I received). The cerussite crystals are well formed, and are essentially colorless and transparent, although many of the crystals appear milky from some angles. The ferro-axinite (if that is accurate) is opaque, vitreous, and exhibits a variety of crystal shapes, including melanite garnet shapes. Some of the crystals are heavily striated, and none have the bladed appearance I usually associate with axinite. Perhaps I should call it a mystery mineral! Some limonite is also present, mostly on the bottom.
cer-19 ($ 70.00)
Masif de belle donne, Isere, France
CERUSSITE specimen cer-21
$ 30.00
$ 30.00
Dims: 1.34x1.18x0.75" (3.4x3.0x1.9cm)
Wt: 1.12oz. (31.8g)
Toussit Mine, near Oudja, Morocco
This specimen contains over a dozen nice cerussite crystals, many of which appear hexagonal due to cyclic twinning. There is also a fair amount of barite, in the form of books of thin translucent blades, pinkish-white in color (some stained a rusty orange). The cerussite crystals are transparent, nearly colorless, and have a vitreous luster. Many of the crystal faces are strongly striated, and at least one face shows a stepped, square growth pattern.
cer-21 ($ 30.00)
Toussit Mine, near Oudja, Morocco
CERUSSITE specimen cer-20
$ 25.00
$ 25.00
Dims: 1.31x0.92x0.56" (3.32x2.33x1.43cm)
Wt: 0.53oz (15.0g)
Toussit Mine, near Oudja, Morocco
This is an excellent small specimen of cerussite. It is a cluster of deeply striated clear and slightly gray-tinted crystals with excellent form. They do have a thin coating of some black mineral, especially in tiny pits on the surface, and the resulting effect is that the crystals appear translucent instead of clear. There are a few places where one can see into the interior, at least with the aid of a loupe. The cluster of cerussite crystals is nestled on a base of barite blades, which are white and translucent but stained a rusty orange. The contrast is very nice.
cer-20 ($ 25.00)
Toussit Mine, near Oudja, Morocco