MINERAL SPECIMENS FOR DISPLAY
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Fluorescent Specimen
= Radioactive Specimen
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INESITE N’Chwaning II Mine, Kalahari Manganese Field, Northern Cape Province, Republic of South Africa Hundreds of very sharp, prismatic, orange-pink terminated Inesite crystals are standing upright, completely covering the top surface of a natural shard of rock matrix, on each specimen. Associated minerals include minor amounts of white Calcite and/or Barite, sometimes visible around the edges of the specimens, or deposited on the back of the matrix. For background information on this occurrence, see the "Mineralogical Record" magazine, Vol. 22, No. 4, P. 287 (July-August 1991). Additional information and color photos can be found in "The Manganese Adventure - The South African Manganese Fields", by B. Cairncross, P. 155 and 160-161 (1997).
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CASSITERITE Elsmore, New South Wales, Australia Several extremely lustrous, dark brown, twinned Cassiterite crystals are intergrown, clustered near the top of the matrix. The largest crystal measures 5/8" wide X 3/8" thick. Dana locale. Size: 1 1/4" tall, 1 1/8" wide, 3/4" thick. Order item MI-058 $60. |
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BISMUTH Wolfram Camp Mine, Queensland, Australia (Dana locale) These excellent examples of native Bismuth are from a deposit in Queensland where rich masses of metallic silvery-gray native Bismuth were formed in open voids, within a large body of crystallized Quartz. Most of the specimens have very obvious, large flat faces which are the impressions of large, prismatic Quartz crystal faces, i.e., the native Bismuth was deposited after the Quartz, in large open voids between the Quartz crystals. Other specimens, like items D. and F., have parallel grooves -- these are possibly the negative impressions (casts) of the stepped faces on large Quartz crystals. Items D. and E. have the negative impressions of Quartz crystal terminations in the Bismuth. This is very obvious in the photo of item E. -- the impression of a smaller Quartz crystal termination is present on the back of the specimen, on item D., as oriented in the photo. Some specimens have minor amounts of crystalline/massive brown Wolframite associated, and/or small amounts of massive white Quartz. Metallic lead-gray massive Molybdenite richly coats one of the flat surfaces of the specimen, on item C. Item A. exhibits the bright, metallic silvery natural cleavage of the native Bismuth on the front of the specimen, as shown in the accompanying photo, while the sides and back of the specimen are in natural condition, as collected. On all other specimens, the natural form of the specimen is the shape of the cast of the Quartz or Wolframite, with very little or no cleavage faces present. The gram weights are given below, as an additional size measurement, for your information. 448.00 grams = 1 pound . . . . item G. weighs approx. 1 pound, and item H. weighs approx. 1 1/4 pound! Order item MI-059, A. through H.
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MALACHITE pseudo after AZURITE with
MIMETITE, DUFTITE, CERUSSITE Tsumeb, South West Africa (Namibia) Deep emerald green Malachite has completely replaced more than 10 sharply terminated Azurite crystals, which were formed in random, upright orientation, covering much of the surface of the matrix. Most of the Malachite after Azurite crystals range in size from 1/4” to 1/2”, 5/8”, and up to 3/4” across. The largest crystal (in the center of the specimen) measures 1 1/4” wide X 1” tall X near 1/2” thick. Rich crystallization of secondary Mimetite and Duftite are associated on the base of the specimen. The obvious white pinpoints seen on the Malachite pseudomorphs are micro Cerussite crystals. Size: 3” X 1 7/8” X 1” thick Order Item MI-060 SOLD |
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