= Fluorescent Specimen
Photos are of typical specimens and do not relate to the specimens described on the list.
The Nördlinger Ries is a large circular depression in western Bavaria, Germany, located north of the Danube in the district of Donau-Ries. The city of Nördlingen is located about 6 kilometers (3.7 miles) southwest of the center of the depression.
The depression is interpreted as a meteor impact crater formed about 14.3 million–14.5 million years ago in the Miocene. The crater is most commonly referred to simply as the Ries or Ries crater. The original crater rim had an estimated diameter of 24 kilometers (15 miles). The present floor of the depression is about 100 to 150 meters (330 to 490 feet) below the eroded remains of the rim. It was originally assumed that the Ries crater was of volcanic origin. In 1960 Eugene Shoemaker and a colleague showed that the depression was caused by a meteorite impact. Another impact crater, the much smaller (3.8 km diameter) Steinheim crater, is located about 42 km (26 miles) west-southwest from the center of Ries crater. The two craters are believed to have formed nearly simultaneously by the impact of a binary asteroid.
Recent computer modeling of the impact event indicates that the meteorites probably had diameters of about 1.5 kilometers (4,900 feet) (Ries) and 150 meters (490 feet) (Steinheim), had a pre-impact separation of some tens of kilometers, and impacted the target area at an angle around 30 to 50 degrees from the surface in a west-southwest to east-northeast direction. The impact velocity is thought to have been about 20 km/s (45,000 mph). The resulting explosion had the power of 1.8 million Hiroshima bombs, an energy of roughly 2.4x10^21 joules.
The Ries crater impact event is believed to be the source of moldavite tektites found in Bohemia and Moravia (Czech Republic). The tektite melt originated from a sand-rich surface layer and was ejected to distances up to 450 km (280 miles) downrange of the crater.
The moldavite specimens offered here are of
excellent quality, translucent-transparent, olive-bottle green color
specimens exhibiting attractive natural, irregularly shaped features on all
sides. All are in natural condition, as field collected. All specimens
have tiny edge chips, but are perfect for reference collection. With a
hardness of approximately 5.5 to 6.5 on the Mohs hardness scale, they are
also highly recommended for jewelry fabrication. The accompanying
photographs illustrate typical moldavite specimens – none of the specimens
offered here are illustrated in the photos.
Fisher Mtn., near Mt. Ida, Montgomery Co., Arkansas
Attractive grouping of colorless Quartz crystals (largest is 2 3/4" tall X 1" in diameter), without matrix. Size: 2 1/2" X 2 1/2" X 2"
Order item MS-002 List Price: $60. Discount Price: $48.
Khorat Plateau, Nakhom Ratchasima Province, Thailand
These perfectly formed oval, to round, to "cigar" shaped, very shiny black examples of the Indochinite variety of Tektites are very attractive for display or reference collection, with interesting pitted surface features.
List Price: $1.00/gr. Discount Price: 80c/gr.
|PREHNITE after ANHYDRITE
Lower New Street Quarry, Paterson, Passaic County, New Jersey Light lime green color crystallized Prehnite has formed several stalactite-like molds after prismatic Anhydrite crystals. The three longest Prehnite molds each measure approximately 1” in length, and are +/- 3/8” in diameter, oriented in an upright position. All of the Prehnite molds are 100% hollow, and the forms of the original, individual Anhydrite crystals are very sharply reproduced --- visible on the base of the specimen (no rock matrix). Dark green hexagonal crystals of Chlorite form numerous microscopic rosettes, “peppered” all over the top of the crystallized, stalactite-like Prehnite. For background information, see the “Min. Record” magazine, Vol. 9, P. 165-166, and Fig. 22 on P. 171.
Size: 2 3/8” X 1 3/4” X 1 1/4”
Order Item MS-004 SOLD
Lucin District, Box Elder County, Utah
This multi-colored, bright green nodular mass of Variscite has been freeform polished on the front of the specimen, for display purposes. The back of the specimen has also been worked, but has a matte luster, rather than a bright polish. The natural gray matrix which is shown in the bottom of the photo, as oriented in the accompanying photograph, extends around the back, and covers about 30% of the back of the specimen.
Size: 3 1/2" tall X 2 3/8" wide X up to 1" thick.
Order Item MS-005
List Price: $40. Discount Price: $25. SOLD
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