Brian Greenstone's Photo Gallery
MGX-V3KCalcite CaCO3 , Quartz SiO2
Dimensions: 70 mm x 98 mm x 52 mm
Weight: 224 g
A beautiful double-calcite on quartz from a one-off pocket at the Borieva Mine in Bulgaria! This pocket was discovered in late July of 2017. There are two large calcite crystals growing on top of each other forming a curved chain. In back of the calcite crystals is a bed of finger-like quartz crystals with green chlorite inclusions. The scalenohedral calcite crystals are yellow-amber color, and are comprised of hundreds of flattened, stacked rhombohedrons. A highly aesthetic, beautiful, and unique specimen! Very good condition with no significant damage.
0TC-7C1Baryte BaSO4 , Fluorite CaF2
Dimensions: 69 mm x 80 mm x 81 mm
Weight: 328 g
This is one of the finest Illinois fluorite specimens that we have ever had for sale! It is absolutely exquisite! There are two fluorite corners growing from a shared stalk that has been partially dissolutioned away. The fluorite has extremely sharp and clear phantoms with a yellow core followed by a thin purple zone and then the blue outer zone. There are two white, round barite balls embedded in the yellow zone just poking through the purple zone. The outer zones are so glassy that light goes right through to the barite balls giving them a very 3D appearance of floating inside of the fluorite crystal.
The condition is also quite superb with very sharp and straight edges and corners. The specimen is of such high quality that you don't even need to put it in a display case under a direct spotlight to get the full effect. Just regular lighting on any shelf lights this specimen up revealing it's incredible beauty!
VA7-G66Prehnite Ca2Al2Si3O10(OH)2 , Epidote (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Dimensions: 66 mm x 78 mm x 39 mm
Weight: 230 g
We've sold many prehnite specimens over the years, but this one definitely ranks among the best! It's quite large for a cluster, and it consists of 11 primary spheres with a few other "bumps", and the form resembles "Charlie Brown" or a Teddy Bear. The larges ball is 4cm wide! Included in the prehnite spheres are thin, black, needle-like epidote crystals. The specimen is in extremely good condition with only one tiny scuff on one of the crystals. The crystals do have internal fissures which is quite normal for prehnite crystals of this size.
ALD-0HGQuartz (Var: Chalcedony) SiO2
Dimensions: 119 mm x 90 mm x 58 mm
Weight: 340 g
Go to any mineral show and you're bound to see lots of "grape agate" chalcedony specimen from Indonesia, and after a while they all start to look the same. However, this one is extremely special and extraordinary! The first thing everyone says when they first see it is that it looks like a heart - not a Valentine's Day heart, but a real heart, so at some point as it traded hands someone named this "El Corazon del Mar" which means Heart of the Sea, and that's exactly what it looks like. While the heart shape does come though in a 2D photo, in person it really looks like one.
The other thing that makes this specimen special is the color. Most of these Sulawesi grape agates are purple, but this one is primarily a teal shade of blue which is unusual. The specimen is almost a complete floater, but it has one very small contact point on the backside. Other than that, it is in perfect condition with no damage that we could spot. Another thing that the camera can't capture is the sparkly / velvety appearance of the chalcedony. The heart section is a matte texture while the bubbly chalcedony area sparkles like crazy! This is an awesome specimen!
FR6-L30Beryl (Var: Emerald) Be3Al2(Si6O18)
Dimensions: 109 mm x 81 mm x 66 mm
Weight: 254 g
Wow! That's all we could say the first time we saw this incredible Emerald specimen from Brazil! Whenever you see Brazilian emerald like this it is either a broken single crystal, or it's a conglomeration embedded deep in matrix. This one, however, is the only one we've ever seen where a preparer when though the trouble of removing all of that matrix to reveal the entire crystal cluster in its full glory, and it is really outstanding.
There are 9 major emerald crystals along with a few minor ones, and they are all either connected to each other or connected to the black mica matrix on the bottom. The emerald crystals are opaque green with black veins - typical Brazilian emerald, and the condition is quite good, but there are a few repairs. Luckily, the repairs were expertly done, so it's difficult to spot where they are, and they certainly don't affect the appearance of the piece whatsoever. If you're looking for a unique Emerald mineral specimen then this is it!
A92-UXQOpal SiO2·nH2O , Quartz (Var: Chalcedony) SiO2
Dimensions: 55 mm x 86 mm x 57 mm
Weight: 232 g
This is the strangest Hyalite Opal specimen we've seen because unlike most specimens which are an amorphous blob of hyalite this one actually has a form, and a quite unusual one at that. It looks like some sort of alien soft-boiled egg. The hyalite in the center is a translucent yellow-orange color, and it is wrapped on the sides by a layer of clear, mostly colorless hyalite. This gives the illusion of a bizarre, alien egg yolk. The hyalite is backed by a chalcedony matrix.
The condition is extremely good with only one possible contact or ding point near the top-left side of the specimen, but it is hard to see unless you look closely for it. Otherwise, there does not appear to be any damage, and the clarity and luster are excellent!
GX9-1JNCalcite CaCO3 , Palygorskite ◻Al2Mg2◻2Si8O20(OH)2(H2O)4·4H2O , Romanèchite (Ba,H2O)2(Mn4+,Mn3+)5O10
Dimensions: 95 mm x 173 mm x 81 mm
Weight: 1158 g
There are many forms of calcite mineral specimens in the world, but none so immediately identifyable as the multigenerational twinned calcites from the Palmarejo Mine in Mexico. One look at these and you know exactly what it is and where it came from because there are no other calcite specimens in the world that look anything like this!
These specimens first started appearing in 2014, but most hit the market in 2017. Even then it was unclear exactly what these were, so most dealers labled them simply as calcite. Recent reseach, however, has revealed exactly what these are and how they formed, and there is an entire article with all of the details in the Sept/Oct 2018 Issue of Rocks & Minerals magazine. According to this research these specimens started as elongated "fish-tail" twinned calcite crystals. Later, more layers of manganese rich calcite were deposited. After this is when things got interesting because there was a uni-directional flow in the cavity where these formed, and this caused a thin, white layer of Palygorskite to form just on one side of the specimen - the side facing the flow. It seems that nothing else could grow on top of the Palygorskite, so subsequent generations of minerals were only deposited on the uncoated surfaces. The thin black layer you see around the white palygorskite is Romanechite, and then after that a new layer of clear/brown calcite was deposited.
This particular specimen is special because it forms a really apparent heart shape with perfect symmetry and aesthetics. The vast majority of these calcite specimens are, well, ugly and damaged. This is one of the few that are in excellent condition with great aesthetics. It's really one of the top examples we've ever seen which is why we acquired it. The main twin calcite crystal is exceptionally large, and the last-generation calcite on the back is clear with some manganite inclusions while the tips are light brown. Even the bottom is caoted with glassy-clear crystals. This is one of the best Palmarejo calcite specimens out there!
LAE-KUYQuartz (Var: Amethyst) SiO2 , Chalcopyrite CuFeS2 , Aragonite CaCO3
Dimensions: 80 mm x 132 mm x 48 mm
Weight: 242 g
The amethyst crystals bear some resemblance to those from Guerrero or Vera Cruz, but this specimen comes from the Tiro de Arcangeles Mine in La Luz. AThe pale purple amethyst crystals shoot upward like fingers from a matrix of partially dissolved calcite and there are chalcopyrite crystals of various sizes. The chalcopyrite crystals appear matte black, and this may be due to an acanthite coating. You can see the iridescent chalcopyrite showing through in some places, especially on the backside's contact area. Just so you know, the ID cards from previous owners all state that the white mineral is calcite, however, we think it may actually be aragonite.
The specimen's provenance is well documented. It was originally acquired in 1994 by collector Ray Berry, and more recently it was acquired by Joe Dorris.
R29-E5ARhodochrosite MnCO3 , Manganite Mn3+O(OH)
Dimensions: 113 mm x 75 mm x 45 mm
Weight: 372 g
N'chwaning rhodochrosite specimens are the most sought after rhodochrosites in the world and large specimens of good quality are extremely rare. This one is not only an excellent size, but it has the extra benefit of being heart-shaped which is quite approprite for such a red mineral specimen. This is the wheat sheaf habit of rhodochrosite crystals, and they're growing on a matrix of black manganite. There are also black manganite specks mixed in with the rhodochrosite, and also some quartz deep in the crevices between the individual rhodochorisite crystals.
As is always the case with red minerals, the exact color is difficult to describe because it depends on the lighting used to view it. Here in my office as I write this description the specimen us under my desk lamp, and the color is exactly as it appears in the photos: a deep, almost cherry red color, but not quite. There's a hint of orange in it. If you watch the video you can see how it appears in our display case. The specimen looks amazing in any lighting, really. In addition to great color, the condition is also excellent. There is no damage or dings anywhere on the face of the specimen, and even the edges are in great shape because whoever trimmed the specimen went to the trouble to keep as many crystals intact as possible.
NMK-FTAQuartz (Var: Amethyst) SiO2
Dimensions: 135 mm x 205 mm x 105 mm
Weight: 1092 g
