Rare Mineral Gallery 1

click on images for larger views

close-up image is 2.5 x 1 mm

ASBEC9-1  Asbecasite  $95

Mount Cervandone, Devero Alp, Baceno, Ossola Valley,
Verbano-Cusio-Ossola Province, Piedmont, Italy

6.3 cm x 3 cm x 3 cm; largest crystal size ~ 1 mm

This specimen hosts numerous diamond-shaped crystals of rare, yellow-tan Asbecasite (Ca₃(Ti,Sn⁴⁺)Be₂[(AsO₃)₃|SiO₄]₂) on a fragment of quartz from the Italian Alps.  It is best appreciated if you have a loupe or a microscope, although the crystals are naked-eye visible. The name Asbecasite is a combination of some of the chemical elements in it: As+Be+Ca+Si, perhaps an example of mineralogists' humor?

click on images for larger views                                               image on right is 16 x 13 mm

image on left is 3 x3 mm                                                                             image on right is 10 x 9 mm

OLIV9-1  Olivenite on Barite $32

El Guanaco Mine, Guanaco, Santa Catalina, Antofagasta Province, Antofagasta Region, Chile

6.0 cm x 3.1 cm x 3.5 cm;  largest Olivenites = 1 mm

Sharp tabular crystals of olive-green Olivenite (Cu₂[OH|AsO₄]) are abundantly scattered over chunky Barites (BaSO₄).

click on image for larger view

LF8-2  Leifite on Polylithionite and Rhodochrosite  $95

Poudrette quarry, Mt Saint-Hilaire, Québec, Canada

2.4 cm x 2.5 cm x 1.4 cm

Leifite ((Na,H₂O)Na₆[F₂|Be₂Al₂(Al,Si)Si₁₅O₃₉],) is quite rare, found in half a dozen localities, of which Mont Saint-Hilaire produces the finest specimens.  This thumbnail Leifite fluoresces pale yellow-orange under LWUV.  The matrix contains minor Rhodochrosite (MnCO₃) and Polylithionite (KLi₂Al[(F,OH)₂|Si₄O₁₀]), the latter of which fluoresces yellow under SWUV.  The future of Mont Saint-Hilaire is uncertain; it is possible that no more specimens will be coming out.

click on images for larger views                                                  image on right is 9 x 7.5 mm

VOLB9-1  Volborthite and Chrysocolla $28 RESERVED

La Verde Mine, Copiapó Province, Atacama Region, Chile

3.2 cm x 2.8 cm x 2.4 cm;  largest Volborthites ~ 2-3 mm

Thin, yellow-green crystals of Volborthite (Cu₃[(OH)₂|V₂O₇] · 2H₂O) are scattered on botryoidal Chrysocolla ((Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O) making a pretty little rock.

click on images for larger views                                                  image on right is 2 x 1.4 mm

image on left is 1.6 x 1.2 mm                                                  image on right is 1.5 x 1.2 mm

MR9-1  Miguelromeroite and Ludlockite $125

Veta Negra Mine, Pampa Larga district, Tierra Amarilla,
Copiapó Province, Atacama Region, Chile

5.2 cm x 3.3 cm x 3.3 cm;  largest Miguelromeroites ~ 2-3 mm

Red Miguelromeroite crystals (MnMn₂Mn₂(AsO₃OH)₂(AsO₄)₂·4H₂O, top right photo) are scattered on a matrix of tan Arsenosiderite, white Barite, greenish Pharmacosiderite and massive gray Tennantite and Arsenic (bottom right photo).  Miguelromeroite is found in only 3 locations in the world.  The material from Veta Negra was originally classified as Villyaellenite, and in 2009 was discovered to be in fact Miguelromeroite.  One fibrous, golden spray (bottom left photo) of rare Ludlockite (PbFe³⁺₄As³⁺₁₀O₂₂) completes the ensemble.

 
click on left image for larger view                                                  image on right is 2.4 x 2.5 mm

AESCH9-1  Aeschynite-(Y) and Hematite on Adularia  $55

Lucendro pass, Lucendro Valley, Central St Gotthard Massif, Leventina, Ticino, Switzerland

7.0 cm x 6.3 cm x 3.3 cm; size of largest crystal ~ 1 mm

Amidst tiny Hematite roses on a pretty matrix of translucent white Adularia, can be seen several tabular, brown, mm-sized Aeschynite-(Y)  (Y,Ca,Fe,Th)(Ti,Nb)₂(O,OH)₆ crystals.  This piece is very beautiful under the microscope where you can see the detail in the Hematite roses.  Although the Aeschynite-(Y) crystals are naked-eye visible, much more pleasure can be taken from this specimen with the use of a loupe or a microscope.

click on images for larger views                                                  image on right is 5 x 5 mm

PRIX9-1  Fibrous Mimetite variety Prixite  $24

Saint-Prix, Beuvray, Saône-et-Loire, Burgundy, France

4.8 cm x 4.3 cm x 3 cm

Prixite is a bizarre, fibrous variety of Mimetite (Pb₅[Cl|(AsO₄)₃]).  As a variety rather than a true species, it does not strictly speaking have a type locality, but according to mindat.org, this is the locality from which it was first reported.  It comes with a Diederik Visser label that also lists Pyromorphite, but I can only identify the yellow Mimetite on this specimen.

click on images for larger views

image on left is 2 x 1.5 mm                                                  image on right is 4 x 3 mm

LEM6-1  Lemanskiite (TL) $495

El Guanaco Mine, Guanaco, Santa Catalina, Antofagasta Province, Antofagasta Region, Chile

14 cm x 11.5 cm x 4 cm;  largest crystal ~ 2 mm

This is the largest piece of Lemanskiite (NaCaCu₅[Cl|(AsO₄)₄]· 5H₂O) that I have ever seen.  If people would prefer smaller pieces, I can try dividing it - let me know.  The bright blue is a mat of crystals (as shown in the left close-up), and the lighter blue sections offer crystals separated by matrix (as shown in the right close-up).

click on images for larger views                                                  image on right is 15 x 13 mm

MAL9-11  Azurite, and Malachite pseudomorph of Azurite $26

Remolinos mine, Cabeza de Vaca district, Copiapó Province, Atacama Region, Chile

5.3 cm x 4.0 cm x 2.5 cm

A couple of very pretty, deep blue Azurites (Cu₃[OH|CO₃]₂) in vugs and some sharp green Malachite (Cu₂[(OH)₂|CO₃]) replacements.

click on images for larger views

close-up image is 7 x 3 mm

TILA9-1  Tilasite  $95

Mount Cervandone, Devero Alp, Baceno, Ossola Valley,
Verbano-Cusio-Ossola Province, Piedmont, Italy

5.5 cm x 3 cm x 7 cm; largest crystal size ~ 7 mm

Characteristically curved Tilasite (CaMg[F|AsO₄]) crystals in a couple of bundles up to 7 x 2 mm.  Although Tilasite is a rare mineral, the curved shape of the crystals makes it very distinctive and easy to spot.  Mount Cervandone, which can be accessed both in Italy and in Switzerland, is a classic locality for this species; in fact, the Swiss side of the mountain has the type locality.

click on images for larger views                                                  image on right is 4 x 2.6 mm

PENF10-1  Penfieldite and Boleite $18 RESERVED

Margarita Mine, Caracoles, Sierra Gorda District, Tocopilla Province, Antofagasta Region, Chile

2.2 cm x 1.5 cm x 0.7 cm;  largest Penfieldites ~ 2 mm

Colorless, tapered and striated Penfieldite (Pb₂[OH|Cl₃]) crystals encrusted with micro blue Boleites (KPb₂₆Ag₉Cu₂₄(OH)₄₈Cl₆₂).

Depth of field in all close-ups is achieved with CombineZP freeware.

Next Gallery

or select a gallery from the table below:

Big Rocks	Gallery 1
Tucson 2010	Gallery 2
Bargain Gallery	Gallery 3
Rare Mineral Gallery 1	Gallery 4
Rare Mineral Gallery 2	Fluorescent Gallery 1
West Coast Spring 2010	Fluorescent Gallery 2