Objects

Displaying 301 - 400 of 42079
Cat. # Name Description
301 00.2.11.283.0006 Melanterite Melanterite is one of only a few water soluble sulfate minerals. It forms in the near-surface secondary oxidation zone of ore deposits usually late in their development. In many mines, melanterite is an ongoing precipitate or efflorescent forming white to green encrustations, crystal aggregates and stalactites right on the sides of the mine's shafts. The primary source of the iron for melanterite is iron sulfides such as pyrite, pyrrhotite, marcasite and chalcopyrite. A technique for removing copper from the copper sulfate mineral chalcanthite is responsible for the naming of an alternate name for melanterite. Chalcanthite, like melanterite, is soluble in water and it thus makes a solution of copper sulfate. If metallic iron is added to the solution, then metallic copper precipitates, leaving a solution of iron sulfate. This left-over solution has the same composition as a solution made from dissolving melanterite. The alternate name for melanterite is "copperas", from the Greek meaning "copper water", an allusion to the left-over solution. In a way, this could be thought of as "copper-providing water". Attractive crystals of melanterite with a beautiful blue-green color are know to exist and are sought after. The shades toward blue come from impurities of copper which can substitute for as much as one third of the iron. The more copper, the bluer the crystals. Generally melanterite is known as having a white or green color. Melanterite is also the name of a group of only five monoclinic sulfates of which melanterite is the only somewhat common member. Members of this group have the same basic structure as melanterite, but can have in place of iron, ions of manganese, zinc, cobalt and copper. These are the members of the Melanterite Group: Bieberite (Hydrated Cobalt Sulfate), Boothite (Hydrated Copper Sulfate), Mallardite (Hydrated Manganese Sulfate), Melanterite (Hydrated Iron Sulfate), Zinc-melanterite (Hydrated Zinc Copper Iron Sulfate) PHYSICAL CHARACTERISTICS: Color is white, green, yellowish green or blue-green. Luster is vitreous to silky. Transparency: Crystals are translucent to slightly transparent. Crystal Habits include stubby prismatic or blocky to tabular crystals, sometimes as pseudo-octahedrons. Also acicular, fibrous and capillary and found as encrusting, stalactitic and concretionary masses. Cleavage is perfect in one direct but only distinct in another. Fracture is conchoidal. Hardness is 2 Specific Gravity is approximately 1.9 (well below average). Streak is white. Other Characteristics: Is soluble in water and may deteriorate with absorption of water. The taste has a sweet, astringent and metallic character. Associated Minerals are epsomite, chalcanthite, gypsum, pyrite, pyrrhotite, marcasite and chalcopyrite. Notable Occurrences include Minas de Rio Tinto, Spain; Rammelsberg, Harz Mountains, Germany and Falun, Sweden; and in the United States at Ducktown, Tennessee; South Dakota; Colorado; Bigham Canyon, Utah; Comstock Lode, Lincoln County, Nevada; Butte, Montana; at several mines in Arizona and at The Geysers in Sonoma County and at Leona Heights, Alameda County, California. Best Field Indicators are crystal habit, low density, associations, solubility in water, taste and color.
302 00.2.13.0505 Copper Not found in catalog.
303 00.2.13.500.0006 Pyrite Pyrite in black tourmaline.
304 00.2.13.500.0008 Calcite With iron disseminated, decomposed marcasite present
305 00.2.13.500.0014 Feldspar None
306 00.2.13.501.0006 Carnallite None
307 00.2.13.501.0014 Wolframite None
308 00.2.13.504.0004 Pyrite Granular aggregates (ore). ! thumbnail with quartz.
309 00.2.13.504.0006 Quartz, amethyst None
310 00.2.13.512.0008 Quartz, geode Fragment.
311 00.2.13.513.0003 Sphalerite Hand- nice black crystal cluster. Miniature - calcite cleavage fragment Color: BR
312 00.2.13.528.0001 Quartz None
313 00.2.13.528.0002 Quartz None
314 00.2.13.528.0004 Feldspar Oligoclase.
315 00.2.13.528.0005 Feldspar Oligoclase.
316 00.2.13.528.0007 Calcite Calcite. Dysaralite.
317 00.2.13.530.0003 Vesuvianite None
318 00.2.14.638.0010 Pyrite Concretions, some decomposition similar to 00.2.1.602 (CS 428 4).
319 00.2.14.696.0020 Sphalerite Massive sphalerite cementing pieces of matrix. Color: BR
320 00.2.14.697.0020 Quartz, geode Quartz geode lined with botryoidal chaldedony.
321 00.2.14.697.0022 Calcite Grotesque argillo calcareous concretion.
322 00.2.14.697.0023 Calcite Argillo-calcareous concretions.
323 00.2.14.697.0024 Limonite One-half large concretion. Color: BR
324 00.2.14.697.0027 Hematite Variety martite; shows octahedrons clearly. Color: BR
325 00.2.15.294.0003 Calcite Concretions; "From a layer just above ferrous sand running into blue Kansanan Clay, and west up into Iowa ten or more feet above it. Now a line of gravel which I had considered B. G. After a while this calcareous matter moves out and underated layers of for. sand takes its place."
326 00.2.15.297.0005 Marcasite Nodule.
327 00.2.15.297.0009 Pyrite Interesting cluster of darkened crystal cubes.
328 00.2.15.298.0003 Quartz, geode Bitumen, bearing geode.
329 00.2.15.298.0007 Quartz Quartz, geode. Peculiarly encrusted crystals.
330 00.2.15.299.0003 Marcasite Nodule.
331 00.2.15.303.0003 Barite Barite/sandstone rose.
332 00.2.15.304.0001 Calcite Concretion about a root
333 00.2.15.304.0003 Calcite Vein, in coal.
334 00.2.15.304.0004 Calcite Vein filling.
335 00.2.15.304.0009 Gypsum Concretion.
336 00.2.15.306.0002 Bournonite Massive, metallic luster; dark gray with pyrite.
337 00.2.15.306.0006 Hematite Botryoidal. Color: RD-BR
338 00.2.15.307.0008 Marcasite Nodule.
339 00.2.15.309.0009 Limonite Fibrous.
340 00.2.15.318.0008 Copper Quartz.
341 00.2.15.318.0009 Copper Native copper.
342 00.2.15.318.0014 Copper Native copper.
343 00.2.15.327.0003 Calcite [Cephenomenal boulderet.(original catalog description)] Calcite crystals with vitreous encrustation on dark massive limestone/dolomite. Color: ML
344 00.2.15.328.0001 Pyrite Iron pyrites, fossil?
345 00.2.15.330.0001 Quartz Illustrative materials.
346 00.2.15.330.0002 Quartz Geodes.
347 00.2.15.330.0005 Dolomite White dolomite crystals covering specimen.
348 00.2.15.330.0008 Dolomite None
349 00.2.15.330.0009 Dolomite None
350 00.2.15.330.0010 Dolomite None
351 00.2.15.330.0011 Barite Misidentified as dolomitic material.
352 00.2.15.330.0012 Barite Misidentified as dolomitic material.
353 00.2.15.331.0002 Wulfenite None
354 00.2.15.331.0003 Scheelite Pale gray, massive.
355 00.2.15.331.0007 Wulfenite Small, golden cubes in vugs.
356 00.2.15.331.0008 Heulandite None
357 00.2.15.331.0009 Nickeline Massive. Color: PK-OR
358 00.2.15.331.0011 Diopside (Pyroxene group) Pyroxene, var. Diopside.
359 00.2.15.331.0012 Aragonite 277 Aragonite CaCO3, Cianciana, Sicily, Foote, Philad'a. Label says dana 814 Scheelite, Tetragonal, Ca WO4, Zinnwald, bohemia. Card says Dana 814, Ward, Tetragonal, scheelite, Ca WO$, Zumwald, Bohemia see 331-13.
360 00.2.15.331.0013 Aragonite None
361 00.2.15.331.0015 Aragonite Twinned crystals.
362 00.2.15.331.0016 Realgar Massive on matrix, glassy coating. Color: RD
363 00.2.15.334.0004 Garnet group Color: YL
364 00.2.15.334.0010 Almandine (Garnet group) Crystals in nephelite - syenite matrix. Color: RD BR
365 00.2.15.696.0007 Calcite Catalog says "Two cards present. One says: Drusy surface of carboniferous limestone, Mahaska Co., Iowa. The other says: dogtooth spar on iridescent surface of limestone."
366 00.2.15.696.0019 Copper None
367 00.2.15.696.0020 Sphalerite Massive sphalerite cementing pieces of matrix. Color: BR
368 00.2.2.560.0004 Pyrite Similar to 00.2.1.602 but listed in old notebook as "astrocarpus" ???
369 00.2.2.562.0012 Columbite (Tantalite group) Massive. Color: BK
370 00.2.2.563.0004 Enargite Dark gray, massive.
371 00.2.2.563.0013 Autunite Yellow flat crystals scattered on matrix.
372 00.2.23.700.0001 Calcite Geode.
373 00.2.23.700.0004 Skutterudite Massive. Color: SL-YL
374 00.2.23.700.0006 Skutterudite Massive; var. smaltite. Color: SL-YL
375 00.2.23.705.0012 Nickeline Massive. Color: YL
376 00.2.23.705.0019 Muscovite Microcrystalline. Color: YL
377 00.2.23.705.0024 Siderite None
378 00.2.23.705.0029 Barite Massive, pink.
379 00.2.23.706.0006 Muscovite Muscovite mica.
380 00.2.23.707.0012a Gypsum Curved crystal groups on matrix, selenite.
381 00.2.23.708.0006 Pyrite Stalactite
382 00.2.23.708.0007 Pyrite Stalactite
383 00.2.23.708.0008 Pyrite Stalactite
384 00.2.23.708.0009 Pyrite Stalactite
385 00.2.23.708.0010 Pyrite Stalactite
386 00.2.23.708.0011 Pyrite Stalactite
387 00.2.23.708.0012 Pyrite Stalactite
388 00.2.23.708.0013 Pyrite Stalactite
389 00.2.23.708.0015 Pyrite Stalactite
390 00.2.23.708.0016 Pyrite Stalactite
391 00.2.23.708.0017 Pyrite Stalactite
392 00.2.23.708.0018 Pyrite Stalactite
393 00.2.23.709.0010 Chalcopyrite Crystals on dolomite crystal matrix.
394 00.2.23.710.0001 Quartz Crystals.
395 00.2.23.710.0004 Quartz Quartz, rock crystals.
396 00.2.23.710.0007 Quartz Botryoidal. Inside of geode.
397 00.2.23.710.0017 Quartz Iron, stained quartz crystals.
398 00.2.23.710.0018 Quartz Geode.
399 00.2.23.710.0024 Aragonite Twinned crystals.
400 00.2.23.714.0001 Halite Massive.
CSV