New Gallery #133

New Photos Gallery Return to mindatnh front page. Click on image for larger view
Photos recently added to NH species galleries, set #133.
COLUMBITE with Sphalerite Colony Mine, Alstead, NH 11 cm specimen. Columbite and sphalerite in feldspar matrix COLUMBITE Colony Mine, Alstead, NH 1.5 cm crystal COLUMBITE Colony Mine, Alstead, NH 2.6 cm specimen COLUMBITE Colony Mine, Alstead, NH 1.5 mm columbite crystal COLUMBITE Colony Mine, Alstead, NH 6.5 mm columbite crystal COLUMBITE Colony Mine, Alstead, NH Label glued to bottom of specimen before breakdown	Species: COLUMBITE Locality: Colony Mine, Alstead, NH Specimen Size: Top photo: 11 cm specimen before break-up. Second photo: 1.5 cm crystal extracted from pegmatite chunk. Other photo sizes as annotated. Field Collected: A purchased specimen from a known friend. Collected 1998. Catalog No.: 2133 Notes: Crystal (second photo) was dislodged in trim from the six inch pegmatite chunk, top photo. The crystal was restored to the matrix for my collection. The surrounding redish-brown mineral is sphalerite. At the May 2020 time of this photo, this is the best-formed, cm plus sized, NH columbite crystal photo known to me [tm]. Two micro-boxed columbite crystals were also extracted from the original 5 pound rock, u2369 & u2370, photos included here. What is interesting, and perhaps significant, is that I can find no instance in mindat's million plus photos of columbite in close association with sphalerite. (and in this Colony Mine case embedded in sphalerite). Jim Nizamoff opined on seeing these photos: "Columbite is not usually directly associated with sphalerite although it often crystallizes in the same zone or area of a pegmatite. Are you absolutely sure that the matrix is sphalerite? Several pegmatites here in Maine contain similar stuff although I don’t recall them having such a direct association (Estes Q is one). I would expect that several NH pegmatites would be capable of producing similar quality columbite (Turner, Chickering, or Chandler) although I doubt that it would be with a ton of sphalerite." Ray Meyers, on seeing these photos, recalled that I had already analyzed this columbite and sphalerite. Checking my EDS notebook (logging over 500 analyses) showed Ray was correct. The EDS analysis of the columbite indicated a chemistry of (Fe_0.53,Mn_0.47)(Nb_0.48,Ta_0.02)O_5.8 . This is close to the midpoint of columbite-(Fe) and columbite-(Mn). The analysis Nb + Ta is low. The APFU was normalized for Fe + Mn = 1. Arrow in the top photo indicates site of analysis grain source. The sphalerite was also analyzed (addressing Jim's uncertainty). The EDS analysis confirmed sphalerite with moderate iron content Zn_0.8Fe_0.2S_1.15 . Checking sphalerite analyses in Dana's System of Mineralogy (Seventh edition, vol 1) there is a ferroan sphalerite: "dark colored varieties with more than ten per cent Fe." The BC analysis indicated 9.97 atomic % Fe... close enough to the 10% threshold that I will call this ferroan sphalerite.
OPAL var. Hyalite Hurricane Mtn. Conway, NH 10 mm field of view	Species: OPAL var. Hyalite Locality: Hurricane Mtn. Conway, NH Specimen Size: 10 mm field of view Field Collected: Leroy Grant - early '70's Catalog No.: NC Notes: A voucher specimen for hyalite opal on Hurricane Mtn. A no stacking photo. This hyalite has a bright green fluorescence in SW UV.
QUARTZ Conway area, NH 4 inch, double-terminated crystal	Species: QUARTZ Locality: Conway area, NH Specimen Size: 4 inch, double-terminated crystal Field Collected: Peter Samuelson Catalog No.: 430 Notes: Purchased from Bill Ross (base of Hurricane Mtn., Conway, NH), May, 1983. $5.00. Possibly from Peter's Dianna's Bath find.
ASTROPHYLLITE Hurricane Mtn., Conway, NH 9 mm field of view	Species: ASTROPHYLLITE Locality: Hurricane Mtn., Conway, NH Specimen Size: 9 mm field of view Field Collected: Leroy Grant -1970's Catalog No.: u2371 Notes: Astrophyllite blades on quartz. Hyalite opal in top rear, crocidolite (blue) in foreground.
ASTROPHYLLITE Hurricane Mtn., Conway, NH 9 mm vertical field of view	Species: ASTROPHYLLITE Locality: Hurricane Mtn., Conway, NH Specimen Size: 9 mm vertical field of view Field Collected: Leroy Grant -1970's Catalog No.: u2371 Notes: Golden astrophyllite hairs in quartz crystal.
RIEBECKITE var. Crocidolite Hurricane Mtn., Conway, NH 2.2 cm field of view	Species: RIEBECKITE var. Crocidolite Locality: Hurricane Mtn., Conway, NH Specimen Size: 2.2 cm field of view Field Collected: Leroy Grant -1970's Catalog No.: u2371 Notes: Mat of blue crocidolite on smoky quartz crystal with astrophyllite.
MUSCOVITE - fine grain Locality: Vacinity of Mascot Mine, Gorham, NH 4.5 cm specimen with green, soft - hardness ~ 2.5, mica in milky quartz matrix. MUSCOVITE - fine grain Locality: Vacinity of Mascot Mine, Gorham, NH 7 mm mica crystal associated with fine-grained mica.	Species: MUSCOVITE - fine grain Locality: Vacinity of Mascot Mine, Gorham, NH Specimen Size: 4.5 cm specimen with green, (soft - hardness ~ 2.5), mica in milky quartz matrix Field Collected: Richard Orsillo Catalog No.: NC Notes: Silvery mica books embedded in fine-grained mica is unusual.
CHABAZITE var. Phacolite Pike-Wilton Quarry, Wilton, NH 5 mm chabazite crystal	Species: CHABAZITE var. Phacolite Locality: Pike-Wilton Quarry, Wilton, NH Specimen Size: 5 mm chabazite crystal Field Collected: Tom Mortimer - 2014 (Authorized visit) Catalog No.: u1490 Notes: A re-do of a 2014 photo. B&L 4X objective, fluorescent ring light, 151 image stack.
ROCKBRIDGEITE Palermo #1 Mine, N. Groton, NH 0.6 mm clump of rockbridge on mitridatite	Species: ROCKBRIDGEITE Locality: Palermo #1 Mine, N. Groton, NH Specimen Size: 0.6 mm clump of rockbridge on mitridatite Field Collected: From a tub of Palermo phosphate rocks gifted by Bob Whitmore Catalog No.: u1889 Notes: A re-do of a 2014 photo. Nikon Plan 10 objective.