MINERAL SPECIMENS FOR DISPLAY

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= Fluorescent Specimen
= Radioactive Specimen

MANGANOTANTALITE
Alto Ligonha Pegmatite Field, Mozambique
Gemmy, transparent, dark magenta-red color single crystal without matrix. The termination and prism faces are sharp. This specimen would probably provide a gem cutter with a nice small faceted stone, but it would make an interesting addition, as a natural crystal, to a display featuring gemstones with their natural mineral counterparts. For background information on the Alto Ligonha pegmatite field, see the "Mineralogical Record" magazine, Vol. 31, P. 459-497 (Nov-Dec 2000). Manganotantalite is described on P. 481-482. This specimen is from the F. Marshall collection.
Specimen size: 7 mm tall, and 4.5 X 4 mm in cross section.
Order Item MI-1009 SOLD

A.

B.

CHRYSOBERYL (twinned)
Tancredo, Santa Theresa County, State of Espirito Santo, Brazil
Several Brazilian localities in the states of Espirito Santo and Minas Gerais are famous for twinned Chrysoberyl crystals. These specimens are both from the F. Marshall collection, purchased in the early 1970’s. Item A. is a heart-shaped twin with the right side of the specimen quite gemmy and transparent yellow. The left side of the twin is translucent yellow, and the specimen has no matrix. Item B. is an excellent group of three heart-shaped twins, translucent yellow, without matrix. The individual heart-shaped twins on item B. range in size from 1/2" to 3/4" tall. Either specimen could be used for display in an exhibit of natural mineral specimens, along with cut gemstones fashioned from the same mineral. Both are very good "thumbnail" size specimens, and would also provide interesting additions to any collection of gem crystals, or twinned crystals. Sizes are given below: width X height X thickness.

MI-072	SPECIMEN SIZE (INCHES)			SPECIMEN PRICE
A.	5/8	1/2	3/8	SOLD
B.	1 1/4	5/8	near 1/2	SOLD

QUARTZ with RUTILE inclusions (rutilated Quartz), and MONTMORILLONITE
Skalistyi Mine, Polar Urals, Russia
The bright golden Rutile inclusions within this large, light smoky color Quartz crystal are so rich, that the crystal literally looks as if it were filled with golden angel hair! Several of the longest sprays of acicular Rutile crystals are up to 2" in length! All six of the termination faces have been lapped and polished, to provide "windows" so the myriad of golden Rutile inclusions can be seen to best advantage. Three of the prism faces of the Quartz crystal have been polished, and three are in natural condition, exhibiting typical horizontal striations. The crystal is double terminated. The second termination is slightly crude and has not been polished. It has multiple faces, and exhibits some stepped growth, with pale pink Montmorillonite inclusions. There is a photo of a similar specimen from this locality in the new "Mineral Collections of Russia", Part II, Vol. 3 / 2000, Page 44.
Size: 6 1/2" long X 3 1/4" wide X 2 1/2" thick. Weight: 1,397.7 grams (slightly > 3 pounds!)
Order Item MI-073 Price: $275.

FLUORITE
Grimsel Pass, Switzerland
Mined sometime in the early 1970’s, this specimen is from the F. Marshall collection. A single, light pink octahedral Fluorite crystal measuring 5/8" X 5/8" is in a group of intergrown crystals and crystal sections, with a very small amount of white Quartz matrix. The Fluorite crystals are light pink in color, translucent, and have a slightly "frosted" luster. The back of the specimen is flat, and bears the impression of the termination of a Quartz crystal which was apparently present in the pocket during growth of the Fluorite crystals. Oftentimes, Fluorite crystals will become detached from the surface of the Quartz crystals (matrix) over time by the continual thawing and freezing process that goes on each year in the pockets in Alpine occurrences.
Specimen size: 1 1/4" tall, 1" wide, 7/8" thick.
Order Item MI-074 Price: $250.

STEPHANITE
Mina General, Fresnillo, Zacatecas, Mexico
This "thumbnail" size specimen consists of a very shiny, metallic black Stephanite crystal intergrowth with sharp prism faces and termination, without rock matrix or associated mineralization. This specimen was part of the group of silver-bearing minerals we obtained from Dr. Miguel Romero in 1991, and a copy of Dr. Romero’s label will be supplied with the specimen. It is most recently from the F. Marshall collection. See the "Mineralogical Record" magazine, Vol. 22, No.5, P. 390-391 (Sept-Oct 1991) for additional information.
Specimen size: 3/4" tall, 3/8" X 3/8" in diameter.
Order Item MI-075 SOLD