9.9 x 6.9 x 5.4 cm. A 6.0 cm, water-clear, striated selenite blade is aesthetically angled atop a mounded matrix covered with smaller selenite crystals on this fine specimen from Naica and the Consie Prince Collection. The slightly curved composite blades at the tip of the sharp, angled termination are a fascinating feature. There is a fine variety of selenite crystals, including pencils and a doubly terminated crystal, at the base.
On a recent trip to Winnipeg, we picked up 10 very unusual specimens of different sorts from the guy who mines them in the clay of the Red River Floodway. This one has the familiar ball shape, but instead of the normally golden-sherry color, the crystals are gem-clear. A single sharp, gemmy crystal rises in one place to crown the specimen. 4 x 2.8 x 2.8 cm
4.4 x 3.7 x 2.8 cm. From a small pocket collected in 2004, this is an unusual specimen in several regards. Firstly, it is just a very rich proustite for a Mexican locale (though other silver minerals are common enough for Mexico, proustite surely is not). Secondly, it is the only one I have personally seen on selenite, both including it and growing upon a smothered selenite crystal or mass. All in all, a most unusual specimen, that happens also to be red and sparkly, and quite gemmy, when backlit. This is a unique piece in my experience.
The following information is from Peter Megaw:
Gentlemen: I do indeed know this property, being (modesty aside) credited with its discovery. It is perhaps more accurate to say that there are 2 pieces to Platosa. The historic mine, where oxidized mineralization daylighted, produced quantities of gypsum/selenite crystals, many with distinctive black phantoms and/or encrustrations of hydrozincite (and rare but lovely examples studded with blue rice-grain smithsonites). Mike New brought out most of these and I got there when the property owner asked Mike if he knew anyone who might be interested in exploring for more of the high-grade silver-lead-zinc ore his father used to mine. Our exploration was very successful and we found the unoxidized, faulted continuation of the orebodies worked in the historic mine with stellar silver-lead-zinc grades. The "new" mine was put into production in 2005 and by mid-2006 we had reached the #5 Manto where silver grades reached 2.5%! It was there that small pods of proustite were found...both as free-standing crystals and frozen in water-clear gypsum. Most of the larger crystals came from the gypsum zone and the gypsum was leached off. The #5 Manto is now exhausted, except for some corners, and only trace amounts of proustite have been found in the other bodies. The ore contains significant amounts of exceedingly fine-grained native silver in massive acanthite, but I have never seen anything I would call a native silver specimen from here. Perhaps someone is cooking them?
Overall, outside of the 5 Manto, Platosa is remarkable for its lack of significant voids in the ore proper...especially in comparison to its cousins like Santa Eulalia, Naica, San Martin, etc. There aren't really any decent pockets with calcite or fluorite, let along sulfides bigger than a few mm. This can/will probably change, I can perhaps tell you more after my upcoming visit.
However, there are caverns lined with large (2 m) gypsum crystals here and there in the mine...they are a real pain since they are full of water and can flood the mine in minutes. Still working on getting some of these out...unlike Naica, they are heavily included so they are not all that attractive.
10.0 x 8.0 x 2.5 cm. A striking, old-time cabinet specimen of sculptural, water-clear gypsum variety selenite cleavage enclosing dogtooth and pearl spar calcite crystals from a classic New York locality - Lockport in Niagara County. Ex. Mullane Collection and comes with an old Bradley’s label with a January, 1952 date.
8.7 x 5.5 x 3.1 cm. A beautiful cluster of water-clear, golden-yellow, fishtail-twinned gypsum variety selenite crystals is elegantly set on matrix covered with smaller crystals. The crystals reach 3.0 cm. The striking cluster is complete-all-around and is nearly pristine. Highly representative of these recent finds.
11.9 x 7.0 x 4.4 cm. A beautiful and aesthetic cabinet plate from the 1998 find at the Lily Mine of Peru. Three sharp, transparent, wonderfully striated gypsum crystals to 2.5 cm are nicely set on very sparkly, drusy quartz-coated matrix. Tufts and individual crystals of green atacamite are richly strewn across the piece and some of the atacamite is included in the gypsum crystals. The primary, atacamite tuft-included gypsum crystal is indeed, striking. These were at first wrongly marketed as "brochantite inclusions in gypsum".
12.0 x 8.2 x 3.0 cm. An excellent cabinet combination specimen richly covered with lustrous atacamite crystal pinwheels and flat gypsum blades. The scintillating, gemmy, dark emerald-green radiating blades nicely compliment the lighter green needles on this specimen from the Type Locality region - the La Farola Mine in the Atacama Region of Chile. This is a very fine example of this copper chloride species in combination with gypsum and well-known locale.
9.4 x 4.9 x 4.5 cm. This specimen consists of excellent, very aesthetic, razor-sharp, golden color, gem, "fishtail"-twinned crystals of Gypsum sitting atop a "ball" of Gypsum which is comprised of several single bladed crystals. The largest twinned crystal measures 4.3 cm long. This "floater" crystal formed in a calcium clay/sediment and has no point of attachment whatsoever. The color is very attractive for the species as well. The material is typically very fluorescent as well. Ex. Brian Kosnar Collection.
5.7 x 4.5 x 3.0 cm. Some of the best, if not the best, selenite crystals have come from the Naica District of Mexico. This visually striking and sculptural, water-clear, gem-like crystal has riveting side striations and gorgeous, twin-like striations on the sloped face. And the crystal is doubly terminated. The bit of attached gossan matrix is a nice accent. Complete-all-around and nearly pristine. Ex. Jaime Bird Collection.
7.2 x 6.8 x 5.2 cm. Some of the best, if not the best, selenite crystals have come from the Naica District of Mexico. This visually striking and sculptural specimen consists of two, intergrown, water-clear, gem-like, spear-point crystals very aesthetically attached to gossan matrix. The crystals have gorgeous, twin-like striations on the sloped, side faces. Complete-all-around and nearly pristine. Ex. Jaime Bird Collection.
25.8 x 2.1 x 1.8 cm. An old-time, large and impressive selenite crystal from the Crystal Cave of Kentucky. This complete-all-around water-clear, gemmy and lustrous giant is pristine. The striking, rounded, yellow termination area rests atop the colorless body. Private Crystal Cave was acquired by the National Park Service in 1961 and was incorporated into Mammoth Cave National Park. Mammoth Cave and Crystal Cave were found to be connected in 1972. This piece was collected prior to the purchase by the Park Service. Ex. Edwin Skidmore and Robert Batic Collections. Very rare on the market from this locale in this quality. I’ve never seen another, in fact.
6.6 x 6.5 x 3.2 cm. Water-clear, colorless, sharp, glassy quartz crystals to 3.6 cm are beautifully tinted pink by underlying botryoidal rhodochrosite on this striking combination specimen from recent finds at the San Antonio Mine at Santa Eulalia. A stair-step cluster of blocky selenite crystals graces the top of the specimen. The form of the matrix, placement of the quartz and selenite crystals on the colorful rhodochrosite makes this an aesthetic specimen.
5.4 x 5.2 x 1.0 cm. A very rare, old-time Utah specimen of a translucent, complete-all-around, floater selenite disk from the famous Great Salt Lake area. This fine piece has stepped growth-faces and interior, parallel-growth zoning. Very nearly pristine. Ex. Mullane Collection and accompanied by an older, faded Burminco label.
8.2 x 5.9 x 5.2 cm. A stunning selenite, and with incredibly sharp and water-clear, gemmy crystals, from this important new Chinese locality. Much better in person.
11.4 x 5.5 x 4.4 cm. The sculptural, 3-dimensional cabinet wedge of matrix from the well-known Potosi Mine at Santa Eulalia is architecturally covered with two generations of rhodochrosite and nicely accented with lustrous, colorless gypsum. The sharp, pastel-pink rhodochrosite rhombs are coated with a very sparkly, second generation of rhodochrosite botryoids. Classic and showy material from this noted locale. Ex. Consie Prince Collection.
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