Gallery 10 Agates, Geodes & Thundereggs
AD-153 Chalcedony geode $50
Valle de las Plumas, Paso de Indios Department, Chubut, Argentina
8.6 x 5.6 x 3.7 cm
A striking sliced and polished geode from Argentina. The Chalcedony geode is lined with vibrant, rust-red, botryoids with a strong, coffee-colored rim. The locals have given these colorful nodules the name “Orellanita”.
AD-150 Agate with Hematite $75
Horní Hale, Klášterec nad Ohrí, Krušné Hory Mountains, Ústí Region, Czech Republic
12.3 x 10.4 x 3.5 cm
This Agate is unlike any I have seen from the Czech Republic. During an early stage of its formation, membrane-like layers of minerals came off the walls of the cavity, broke and were deposited in a colloidal silica solution. This Agate has a light-blue color that is accented by veins of silver-gray hematite that have colored the Agate red. A very striking and eye-pleasing combination of colors.
AD-145 Amethyst & Chalcedony geode $50
Dugway Mountains District, Dugway Range, Tooele County, UT
10.1 x 7.3 x 2.6 cm
This is one of the most colorful Dugway geodes that I have come across in my 30+ years of collecting. What you typically get with a Dugway are washed out earth tones and if you are lucky, light blue Chalcedony and some small crystals of Quartz. This multi-chambered nodule has a good red-brown hue accented by bands and areas of green with a central chamber of rich-colored Amethyst.
AD-146 Opal nodule $35
Yowah Opal Field, Paroo Shire, Queensland, Australia
6.9 x 3.6 x 1.7 cm
This striking specimen of “Yowah Nut” Opal consists of a Sandstone nodule that is permeated by Opal of many different colors that it makes for a very colorful and aesthetic specimen. This is the first one of these that I have encountered that has a hollow center.
AD-138 Agate & Quartz Thunder Egg $60
Nowy Kosciól, Kaczawskie Mts, Lower Silesia, Poland
8.5 x 9.3 x 4.1 cm
Here we have a multicolored Agate and Quartz Thunder Egg with a small vug at its center. The Agate portion shows fine banding with an inner rim of flame-colored Chalcedony. Nowy Kosciól is a classic Polish locality. Thunder Eggs such as these are highly prized by Polish Agate collectors and are rarely available outside of Europe.
AD-139 Malachite geode $95
Mashamba West Mine, Kolwezi District, Katanga, Democratic Republic of the Congo
4.5 x 3.9 x 3.6 cm
Despite its size, this Malachite geode really has a presence. The vug of this specimen shimmers very much like velvet due to the dense sheaves of micro-acicular crystals. This specimen is solid Malachite with a small crystal of Barite protruding from the edge of the specimen's vug. Specimens such as these are quite uncommon despite the fact that there is so much Congolese Malachite available to collectors.
AD-123 Quartz & Hematite geode $60
Kenfig Sands, Porthcawl, Bridgend, Wales, UK
7.5 x 7 x 2.6 cm.
Here we have a geode that very much resembles the more famous nodules from the Dulcote Quarry which is about 30 or so miles to the southeast. This ocean front location has been known for its geodes since at least the 1800's. According to H.T. De La Beche, in his Memoirs of the Geological Survey published in 1846, he puts forth the theory that these are weathered out of the seabed offshore and wash up on the beach.
AD-148 Agate & Quartz geode $35
Valle Escondido, San Rafael Department, Mendoza, Argentina
5 x 4.6 x 3.8 cm
A very colorful specimen from south America's other agate location, Mendoza Argentina. Agates from this location have a reputation for being as colorful as their Brazilian counterparts.
AD-149 Agate & Amethyst geode $65
Ametista do Sul, Rio Grande do Sul, Brazil
9.1 x 10.5 x 9.2 cm
I acquired this Agate about 10 or so years ago from a friend who imports a lot of material from Brazil. I chose it because I had never seen one of this particular color that had an Amethyst vug at its center. And I have yet to see another like it. It was only recently that it dawned on me that I had seen this material, but it had been made into spheres. Which might explain why I had only seen this one intact geode half.
AD-135 Calcite Geode $60
US Highway 27 Roadcut, McCreary County, KY
11.5 x 9.5 x 5.2 cm.
A really cool specimen. Although it is not apparent in the photo this specimen is very 3 dimensional. Also, the stacked brownish rhombs of Calcite make for a nice contrast against the lining of smaller white Calcites.
AD-143 Opal nodule $350
Spencer Opal Mine, Spencer, Clark County, ID
8.4 x 7.7 x 6.1 cm
When you think of American Opal, the Virgin Valley in Nevada is usually the first to come to mind. This specimen hails from America's other large Opal location, Spencer, Idaho. With a population of 38, it is home to one of the largest Opal deposits in the United States. This is one of the most vividly colored Opals of this size that I've seen from this location. While the center of this nodule is opaque, the rest of the specimen more than makes up for this. This colorful Opal nodule has a strong saturation of color, more than my photographic skills can capture. Broad flashes of green, blue, violet and a little red can be seen no matter how the nodule is oriented. The Opal at this mine are contained in a Rhyolite and Obsidian flow with abundant gas pockets. Hydrothermal fluids from hot spring activity filled the pockets with both common and precious Opal. A colorful specimen that is sure to brighten up any mineral display.
AD-137 Agate Thunder Egg $60
Nowy Kosciól, Kaczawskie Mts, Lower Silesia, Poland
10.2 x 9.2 x 4.4 cm.
A multicolored Thunder Egg type Agate with a hollow center from a classic Polish locality. Thundereggs such as these are highly prized by Polish collectors and are rarely available outside of Europe.
AD-131 Agate with Quartz $75
Sweet Home, Linn County, Oregon
10 x 7.3 x 4.6 cm.
A beautiful translucent nodule of Agate. The vug in the center is lined with lemon-yellow-colored Quartz crystals. I backlit this specimen a little to better illustrate its translucency.
AD-132 Pyrite in clay nodule $60
Ulyanovsk, Ulyanovsk Oblast', Povolzhsky Region, Russia
7.5 cm. x 8.5 cm. x 5 cm.
AD-147 Calcite geode $35
Bou Azzer District, Tazenakht, Ouarzazate Province, Drâa-Tafilalet Region, Morocco
9.5 x 4.7 x 7.2 cm
A geode filled with many lustrous and clear crystals of Calcite measuring up to 1.7 centimeters in size. If you examined, in person, the matrix that these occur in you'd be surprised that they can be extracted more or less intact.
AD-072 Calcite Geode $50
St. Francisville, Clark County, Missouri
9 x 6 x 4 cm.
A showy specimen of translucent and lustrous Calcite crystals inside of a Quartz-lined Geode. This specimen is from an obscure location and is older material that is not often seen for sale.
AD-126 Chalcedony, Agate and Quartz $50
Potato Patch, Hauser Beds, Palo Verde Mountains, Imperial County, California
12.5 x 10.4 x 4.7 cm.
While once abundant, the days of easy digging at the Potato Patch are over. These days there is not much to be found there. This example of Chalcedony, Agate and a little cit of coarsely-crystallized Quartz is classic, older material that Agate & Thunder-egg collectors hold in high regard.
AD-133 Agate SOLD
Juchem Quarry, Niederwörresbach, Herrstein, Hunsrück, Rhineland-Palatinate, Germany
6.5 x 3.4 x 2 cm.
The region surrounding Idar-Oberstein has been a source of colorful and interesting Agates for nearly 500 years. This interesting example features a light coffee-creamy colored Agate with a red area near the center of the vug. You don't seem to see many examples of German Agates for sale here in the United States.
AD-089 Agate with Amethyst $60
Steinkaulenberg, Idar-Oberstein, Hunsrück, Rhineland-Palatinate, Germany
8.2 x 7.1 x 3.7 cm.
Here's something that you don't see for sale very often. The area surrounding the twin cities of Idar & Oberstein gained notoriety for the fantastic Agates & Amethyst lined geodes discovered there in the mid 1500's. By the beginning of the 1800's the production of material had fallen to a small fraction of what was found in its heyday. This polychromatic Agate features finely banded layers of gray, white and pink culminating with a vug of tiny Amethyst crystals in its center. While occasional specimens can be found, there is no steady supply of material from this classic location.
AD-141 Opal Thunder Egg $30
Opal Butte, Morrow County, OR
5.5 x 4.7 x 2.4 cm
One thing that Oregon has an abundance of is Thunder Eggs. There are plenty of Thunder Eggs that are filled with Quartz and Agate, but not many that are filled with Opal. This specimen has very subtle pink-colored flash.
AD-113 Agate and Quartz geode $75
Lierbachtal, Oppenau, Schwarzwald, Germany
13 x 12 x 3 cm.
Here we have a very large section of Agate from Germany's Black Forest. The center of this slate-colored Agate is filled with Quartz crystals. The section of this Agate that has the Quartz crystals is outlined by a red-colored mineral, most likely Hematite. In my 23 years of collecting I have only seen one other example of this material. There are many Agate localities all over Germany, but few Agates ever make it to the United States.
AD-118 Agate and Quartz geode $25
Iraí, Alto Uruguai Region, Rio Grande do Sul, Brazil
6.2 x 5.4 x 4.5 cm.
While it is true that Agate specimens from Brazil are very abundant, every once in a while you find examples that are more interesting than most. A while back, while visiting with a friend of mine that has a shop in San Diego, he showed me about 50-60 Agates that had been polished all around, not just on the front face. As a rule, I don't buy Agates from Brazil, but I was impressed enough with what he showed me to buy a half dozen of them. This specimen has an outer band of light- blue with a sandy-yellow colored bands, followed by clear Quartz at the center where there is a cavity lined with a druse of small Quartz crystals. Not your everyday Agate from Brazil.
AD-104 Quartz, Hematite & Calcite nodule $125
Dulcote Quarry, Wells, Somerset, England
13.5 x 11.7 x 7.6 cm.
Often referred to as “Potato Stones” by the local collectors because the outer portion of these nodules resemble a potato. Although there are many of these to be found in the hills & surrounding valleys, these once abundant geodes and nodules are almost never seen for sale these days. This is due to the fact that the main deposits are either located on private property or in quarries, making it almost impossible to collect specimens. The geodes and nodules from this classic location are much prized by collectors due to their colorful nature and endless arrays of circles and bands that make each one of these specimens truly unique.
AD-101 Dolomite and Quartz geode SOLD
Warsaw, Hancock County, IL
7 x 5.3 x 4.6 cm.
One of the more obscure geode locations in the midwest is Warsaw, Illinois which is a little bit south of and just across the border from the more famous, classic locality, Keokuk, Iowa. The Warsaw geode areas have yielded some pretty good specimens over the years. This specimen that I am offering here is one of the best looking Dolomite geodes that I have seen from this locality. This specimen consists of a shell of Calcite with a layer of tiny, clear and sparkly, Quartz crystals which serve as a host for numerous, curved, Dolomite crystals. A top-notch specimen from America's mid-west.
AD-087 Agate with Quartz $35
Idar-Oberstein, Rhineland-Palatinate, Germany
11.2 x 7.5 x 3.5 cm.
Here's something that you don't see for sale very often. The area surrounding the twin cities of Idar & Oberstein gained notoriety for the fantastic Agates & Amethyst lined geodes discovered there in the mid 1500's. By the beginning of the 1800's the production of material had fallen to a small fraction of what was found in its heyday. This specimen features finely banded gray, white and pink Agate alternating with layers of Quartz. While occasional specimens can be found, there is no steady supply of material from this classic location.
AD-088 Agate $30
Idar-Oberstein, Rhineland-Palatinate, Germany
7.2 x 5.4 x 5.6 cm.
Here's something that you don't see for sale very often. The area surrounding the twin cities of Idar & Oberstein gained notoriety for the fantastic Agates & Amethyst lined geodes discovered there in the mid 1500's. By the beginning of the 1800's the production of material had fallen to a small fraction of what was found in its heyday. This polychromatic Agate features finely banded layers of gray, white and pink making for a specimen with a striking contrast of colors. While occasional specimens can be found, there is no steady supply of material from this classic location.
AD-090 Agate & Quartz Thunder Egg RESERVED
Saint Egidien, Glauchau, Saxony, Germany
10.1 x 7.8 x 4 cm.
The tortured form of the inner space of this nodule is evidently due to pressure from inside as it formed. This specimen features a band of red Agate and a core of colorless Quartz. This colorful specimen is from the very famous and classic German locality, Saint Egidien. Agates and Geodes from Germany are treasured by European collectors and are not easy to come by.
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