Pseudomorphs and Casts Minerals Gallery M&W Minerals

Pseudomorphs and Casts Gallery

On this gallery, are gathered all the specimens on this website which are considered pseudomorphs. A pseudomorph is a mineral or mineral compound which is in an atypical form, which has resulted from a substitution process in which the appearance and dimensions of one mineral have been retained, but the original mineral is replaced by another. The name literally means "false form". There are essentially 3 kinds of pseudmorphs which are the following:

Substitution Pseudomorphs: In these specimens, one mineral has been completely chemically substituted by another mineral. The shape of the original mineral is retained, but color, hardness, and density are usually different (and often luster).

Alteration Pseudomorphs: In these specimens, only a partial substitution has occurred. This leads to a specimen with a layer of the new mineral with an interior of the original mineral with the shape of the original mineral.

Perimorphs: In these specimens, one mineral has been coated by another and the original has dissolved. This usually leads to a specimen with a mix of surfaces both of the new mineral and the surfaces of the dissolved mineral. A gray area is where this

dissolution is not natural. A case in point, Michigan Copper specimens are often found as casts after Calcite. In some cases, the dissolution has occurred due to acidic natural solutions but in other cases the Calcite has been purposely etched out with acid. Sometimes it is difficult to differentiate between the two.

Casts: In these specimens, a mineral has formed but it's shape has been determined by the environment in which it formed. Two examples are geodes and Michigan Copper Skulls and Amygdules.

minerals in alphabetical order by first letter only
(this is the primary mineral of the specimen - the pseudomorph may be a secondary mineral)

click on the title link or photo to proceed to a specimen's page

A

5412 Aquamarine, Goethite Pseudomorph after Siderite, Biotite

Erongo Mountain, Erongo Region, Namibia
4.6 x 4.4 x 2.8 cm
$85

5396 Aquamarine partially Pseudmorphed to Albite, Tourmaline (likely Foitite)

Erongo Mountain, Erongo Region, Namibia
6.1 x 3.1 x 2.9 cm
SOLD

B

4575 Iridescent Baculites

Pierre Shale, Cretacous Period, South Dakota
Ex. Vivian Randall
5.8 x 3.4 x 1.3 cm
$25

3556 Barite, Quartz

Washington Co., Missouri
8.6 x 9.2 x 7.6 cm
$25

C

5393 Copper Crystals with Casts after Calcite, Chlorite, Microcline, Epidote Caledonia Mine, Ontonagon Co., Michigan 9 x 5 x 4.7 cm $50	5331 Hexagonal Calcite partially Pseudomorphed to Malachite on Chalcopyrite Pseudomorph Casts after Galena Sweetwater Mine, Viburnum Trend Dist., Reynolds Co., Missouri 3.6 x 3 x 3.1 cm $35	5312 Copper Crystrals with Casts after Analcime Seneca Mine, Mohawk, Keweenaw Co., Michigan Ex. A E. Seaman Museum 7.1 x 2.7 x 2 cm $75
5183 Clinoptilolite, Quartz Pseudomorph after Anhydrite, Scepter Quartz, Calcite, Celandonite Planalto, Alto Uruguai region, Rio Grande do Sul, Brazil Ex. Steve Pullman purchased from Luiz Menezes in 1990 at Tucson 6.1 x 3.7 x 2.6 cm $75	4994 Calcite with Unidentified Pink Alteration, Chalcopyrite Sweetwater Mine, Viburnum Trend Dist., Reynolds Co., Missouri 4.2 x 1.9 x 1.5 cm $40	4604 Calcite pseudomorph after Glauberite Camp Verde, Camp Verde District, Yavapai Co., Arizona 9 x 6.7 x 7.1 cm $45
4464 Cephalopod with Dolomite Crystals Traverse City Group Limestone, Devonian, Alpena Co., Michigan Ex. Robert Gannon 9.3 x 3.9 x 2.7 and 7.7 x 4.2 x 2.8 and 5.7 x 3.2 x 3 cm $50	4057 Quartz on Twinned Calcite Crystals on Chalcedony Pseudomorph after Aragonite Cadman Quarry, Monroe, Snowmish Co., Washington Ex. George Katzmarek 5.9 x 5 x 4.7 cm $45	3635 Chamosite Pseudomorph after Almandine Spurr Mountain Mine, Imperial Heights, Baraga Co., Michigan 6.3 x 6.3 x 6.4 cm $35
3371 Chamosite Pseudomorph after Almandine Spurr Mountain Mine, Imperial Heights, Baraga Co., Michigan 5.2 x 4.7 x 4.8 cm $35	3348 Hexagonal Calcite on Dolomite and Chalcopyrite Casts after Galena Sweetwater Mine, Ellington, Viburnum Trend District, Reynolds County, Missouri, USA 11.7 x 5.4 x 3.6 cm Largest XL is 2.6 x 1.2 x 0.9 cm $50	2243 Crinoid Stems Bloomington,Monroe Co., Inidiana, USA Priror to 1975 9.4 x 3.5 x 4.2 cm $35
282 Copper Skull Lake Superior Copper District, Michigan, USA 10.2 x 6.3 x 4.6 cm $175

H

5035 Hardystonite, Clinohedrite, Willemite, Calcite, Franklinite

Franklin Mine, Franklin, Franklin Mining District, Sussex Co., New Jersey
Type Location
UV Fluorescent
Hardystonite: Ca₂ZnSi₂O₇ , Clinoherdite: CaZnSiO₄·H₂O
7.1 x 6.7 x 3.4 cm
$75

L

5330 Limonite Pseudomorph after Marcasite and Spahlerite with Dolomite and Calcite

Fairdale Quarry (I-39 Quarry), Rochelle, Ogle Co., Illinois
5.1 x 5.2 x 4.9 cm
Largest crystal measures 1.2 cm across.
$45

M

5027 Malachite on Quartz with Casts after Calcite, Minor Chalcopyrite Mina El Cobre, Zacatecas, Mexico Ex. Robert Gannon 7.8 x 6.3 x 4.2 cm $45	4629 Malachite Pseudomorph after Azurite Tsumeb, Namibia 5.2 x 2.8 x 1.6 cm $150	4392 Mimetite pseudomorph after Vanadinite Elko County, Nevada Collected by Steve Pullman 6 x 6.4 x 2.6 cm $30
2887 Malachite Pseudomorph after Azurite Tsumeb, Namibia 3.8 x 2.9 x 2.6 cm $250	2508 Malachite Pseudomorph after Azurite Mina Milipillas, Milipillas, Sonora, Mexico 6.3 x 5 x 1.3 cm $75	2062 Mimetite on Goethite pseudomorphs after Calcite Megala Pefka Mine No. 28, Lavrion (Laurion; Laurium) District, Attiki (Attica) Prefecture, Greece Ex. Steve Pullman 6.2 x 6 x 1.5 cm $50

P

5328 Pyrite Pseudomorph after Marcasite, Double Terminated Calcite and Quartz Crystals, Dolomite

Nanisivik Mine, Nanisivik, Baffin Island, Nunavut Territory, Canada
Ex. A. E. Seaman Museum, Lance Hampel collection
15 x 9.8 x 6.4 cm
$375

5316 Prehnite Pseudomorphs

Boyleston Quarry, Barrhead, Strathclyde, Scotland
Ex. H. R. McBroom, Acquired 1978
13.6 x 8.6 x 8.5 cm
$100

5087 Plumbogummite Pseduomorph after Pyromorphite

Yangshuo Mine, Yangshuo Co., Guilin Pref., Guangxi Zhuang Autonomous Region, China
UV Fluorescent
PbAl₃(PO₄)(PO₃OH)(OH)₆
6.5 x 4.3 x 3.4 cm
$200

5044 Pyromorphite Pseudomorph after Cerussute

Higher Roughton Gill (Balliway Rigg), Roughton Gill, Caldbeck Fells, Cumbria, England
5.6 x 4.3 x 3.8 cm
$150

4760 Pyromorphite on Quartz with Casts after Barite

Williams Corners, Wheatley Mines, Phoenixville Mining dist., Schuylkill Twp., Chester Co., Pennsylvania
9.8 x 6.2 x 5.2 cm
$75

4104 Polished Petrified Wood (Chalcedony / Quartz)

Blue Forest, Eden Valley, Sweetwater Co., Wyoming
Pre 1975
10.4 x 7.3 x 1.1 cm
$25

1663 Petrified Wood

Montana
10.5 x 8.4 x 3.8 cm
$15

338 Pyrite pseudomorph after Pyrrhotite

Zacatecas, Mexico
8 x 5.7 x 4 cm
$50

4228 Pyromorphite on Quartz with Casts after Barite

Mexico Mine, Roughton Gill, Caldbeck Fells, Cumbria, England
Ex. H. R. McBroom, from trade with Sam Weller, 1987
7.8 x 6.2 x 3.1 cm
SOLD

Q

5263 Smoky Quartz, Hematite, Copper Stained Chalcedony with Pseudomophs and Casts Mexico (likely Concepcio del Oro, Zacatecas, Mexico) Ex. Robert Gannon 6.5 x 5.8 x 6.4 cm Uprght crystal measures 4.5 cm tall. $75	5064 Quartz and Hematite Pseudomorph after Epidote Bessemer Claim, Bessemer Ridge, Green Mountain, North Bend, King Co., Washington Ex. Steve Pullman 7.7 x 3.8 x 2.2 cm $50	4919 Quartz Pseudomorph after Goethite Stalactit Growths with Attached Flint John Nethers property, Flint Ridge, Hopewell Twp., Muskingum Co., Ohio Collected by J. Medici 6.8 x 6.7 x 6.3 cm The individual stalactites measure 5 to 7 mm in diameter. $85
4857 Quartz Pseudomorph after Anhydrite OS pocket, Ouray, Ouray District, San Juan Mts, Ouray Co., Colorado 13.7 x 5.3 x 1.3 cm $200	3111 Quartz Pseudomorph after Poker Chip Calcite Guanajuato, Mexico 14 x 12.6 x 7.3 cm $75