Petarasite and Polylithionite from Mont St-Hilaire
PAPG5-1 Papagoite $125 SOLD
Mine, Ajo, Little Ajo Mts, Ajo District, Pima Co., Arizona, USA (TL)
This large, rich specimen of Papagoite, CaCu[H3AlSi2O9], is from the type locality (TL). Most of the coverage is in the form of a crust, but as you turn the specimen under the light, you can see the sparkle of many sub-millimeter-sized crystals. Use of a loupe or a low-power microscope reveals their prismatic shapes embedded in the crust.
Little wheat-sheaf clusters, sprays and bowties of pure Pectolite (NaCa2[HSi3O9]) piled on top of each other to form an airy specimen. It fluoresces a sort of pink-yellow-orange under both SWUV and LWUV, more strongly with the latter.
PHEN9-1 Phenakite on Quartz $18 SOLD
Foster, Bennett, Atlin Mining Division, British Columbia, Canada
A Quartz fragment sprinkled with about 2 dozen clear, small Phenakites (Be2[SiO4]) from an unusual locality.
PHOE9-1 Phoenicochroite $32 SOLD
Potter-Cramer Mine, Vulture District
4.8 cm x 4.2 cm x 3.9 cm
A miniature-sized sample with a coating of resinous, red Phoenicochroite, Pb2[O|CrO4]. It requires 60 x on my microscope to discern any crystals, and there are only a few of them hiding out on this specimen.
PhCa9-1 Phosphosiderite and Cacoxinite $75 SOLD
Folgosinho, Gouveia, Guarda District, Portugal
8 x 6.4 x 4 cm
By now you should have guessed that I have a new toy: a digital microscope, as evidenced by the alarming plethora of close-up photos. Purple balls of Phosphosiderite (FePO4·2H2O) and yellow crusts of Cacoxinite (Fe3+24Al[(OH)12|O6|(PO4)17] · 17H2O) decorate this specimen. If you go to the enlargement of the lower left photo and scan the lower right for something resembling a yellow slice of pizza, then you can see the only radial spray of Cacoxinite that I was able to capture in a photo.
Plumbogummite, Mimetite and Pyromorphite $165 SOLD
This specimen of yellow-green Pyromorphite (Pb5[Cl|(PO4)3]) on top of blue Plumbogummite (PbAl3[(OH)5|(PO4)2] • H2O) with orange and yellow Mimetite (Pb5(AsO4)3Cl) dates to about the 1830s and was previously in the Liz and Dave Hacker collection. Much like the recently discovered Plumbogummites of China, this specimen has Mimetite cores coated with Plumbogummite - see the photo in the lower left and look for the yellow circle surrounded by blue just below the photo's center. It also has a patch of orange Mimetite of the variety Campylite. A very rare locality piece only available when collections are recycled.
POSN9-1 Posnjakite $95 SOLD
Mine, Gunnislake Area, Callington District
4 cm x 2.5 cm x 2.8 cm
Posnjakite (Cu4[(OH)6|SO4] · H2O) is an uncommon copper sulfate that forms in the oxidized zone of copper-bearing hydrothermal mineral deposits. This specimen comes with an older-looking label from David New Minerals.
Green Cuprian Powellite (Ca[MoO4]) crystals in vugs. Surprisingly, even with the copper content, the Powellite still fluoresces bright cream-yellow under SWUV.
Nodule $55 SOLD
Wave Hill, Victoria-Birrindudu Basin, Northern territory, Australia
A solid nodule of green Prehnite : (Ca2Al2Si3O12(OH)) with white and brown inclusions. Natrolite is reported from this locality, so that would be my guess for the composition of the pale inclusions, a portion of which is seen in close-up at bottom left. I particularly like the rind on this one since it is unusual to see a Prehnite inside a rind, and it forms a nice frame. This nodule half was in my geode-nodule case when it received first place 4 times at the San Diego County Fair.
PRET9-1 Pretulite $95 SOLD
Mt., Alpl, Freßnitzgraben, Krieglach,
3.4 cm x 2.1 cm x 2 cm
is one of only a few scandium-containing minerals, and this specimen
comes from the type locality for Pretulite. The Pretulite is the
yellowish material. The blue matrix consists of Lazulite in Quartz.
PSB9-1 Pseudoboleite (TL) on Boleite (TL) $55 SOLD
Rosalía, Boleó District, Mun. de Mulegé,
A: 4 mm x 4 mm x 4 mm
Pseudoboleite (Pb31Cu24Cl62(OH)48) is a rare mineral that usually only occurs as sub-millimeter crystals. But in Santa Rosalía, it is found growing epitaxially on Boleite (KPb26Ag9Cu24(OH)48Cl62). Epitaxy is defined as: The growth of a crystal of one mineral on the surface of a crystal of a different mineral in a definite orientation determined by the atomic structures of the two minerals (from Photo-Atlas of Minerals Glossary). What this means for this specimen is that the Pseudoboleite is the raised step found on all 6 six sides. Please specify specimen A (left) or specimen B (right).
Pseudomalachite $36 SOLD
PYR5-10 Pyrite and Calcite $165 SOLD
Nanisivik Mine, Nanisivik, Baffin Island, Nunavut Territory, Canada
I have never seen any better rectangular Pyrites (FeS2) than the ones on this piece. Unlike the basic cubic form, these crystals are elongated in at least one direction, and sometimes have different lengths in all 3 directions, with beveled edges.
Pyrite stalactite $36 SOLD
When mineral-containing liquid drips from the ceiling of a cave, pocket or vug, the droplet leaves behind a ring of deposited minerals that were dissolved in the droplet. This ring eventually grows into a straw-like stalactite formation, gaining thickness if additional flow goes over the outside. This particular stalactite specimen consists of Pyrite (FeS2) crystals growing radially outward from a central hole that runs the length of the specimen. The right-hand photo shows a top view of the specimen, giving a good look at the central hole.
Pyrochlore $65 SOLD
This specimen is a rather large single crystal of the niobium oxide Pyrochlore ((Ca,Na)2Nb2O6(OH,F)). The mineral Pyrochlore is one of the principal ores of niobium, an interesting element that is also called columbium. Niobium is used to confer heat resistance in metal alloys, and we used it in some of our smaller rocket engines when I worked at Rocketdyne. This heavy crystal is an attractive rare mineral – it looks like it was carved out of a lustrous wood.
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