New Gallery #102

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Photos recently added to NH species galleries, set #102.
GENTHELVITE Near Rocky Gorge, Kancamagus Highway, Albany, NH 2.3 mm genthelvite crystal GENTHELVITE Near Rocky Gorge, Kancamagus Highway, Albany, NH 2.3 mm genthelvite crystal	Species: GENTHELVITE Locality: Near Rocky Gorge, Kancamagus Highway, Albany, NH Specimen Size: 2.3 mm genthelvite crystal - two views Field Collected: Bob Janules Catalog No.: A Bob Janules specimen Notes: EDS analyzed by Jim Nizamoff, # JN0014. Zn >> Fe. [tm] Visually, this looks more like danalite, but as analysis showed, looks can be deceiving.
GENTHELVITE Talus slope, N. Sugarloaf Mtn., Bethlehem, NH 1.5 mm field of view	Species: GENTHELVITE Locality: Talus slope, N. Sugarloaf Mtn., Bethlehem, NH Specimen Size: 1.5 mm field of view Field Collected: Bob Janules Catalog No.: A Bob Janules specimen Notes: EDS analyzed # EZS003. ??
STILPNOMELANE Government Pit, Albany, NH 6 mm field of view STILPNOMELANE Government Pit, Albany, NH 3 mm field of view STILPNOMELANE Government Pit, Albany, NH 2 mm field of view	Species: STILPNOMELANE Locality: Government Pit, Albany, NH Specimen Size: 6 mm field of view. Stilpnomelane on microcline. FOV's for zoom views as annotated. Field Collected: Found in large box of uncleaned, untrimmed, Government Pit specimens collected by Leroy Grant of Albany, NH (deceased). Collected in the 1970's. Catalog No.: u2229 Notes: In comparison with mindat.org stilpnomelane specimens, this one is very nice. From a stack of 95 images using a Bosh & Lomb microscope objective with my Canon G9 camera. Stilpnomelane chemistry is (mindat.org): (K,Ca,Na)(Fe,Mg,Al)₈(Si,Al)₁₂(O,OH)₃₆ · nH₂O A carbon tape mounted grain EDS analysis (BC303, set 21) calculated an APFU chemistry of: (K_0.43,Ca_0.56)_Σ=0.99(Fe_4.41,Al_3.79)_Σ=8.2Si₁₂O₁₀₉ , normalized for 12 Si. This computed formula assigns all the Al to the (Fe,Al) group to make the chemistry match best possible. With this convenience, the analysis matches the mindat formula quite well. No Na or Mg substitutions were detected in this Government Pit sample.
FLUORITE Government Pit, Albany, NH 0.6 mm purple fluorite in vug with small balls of green glauconite.	Species: FLUORITE Locality: Government Pit, Albany, NH Specimen Size: 0.6 mm purple fluorite in vug with small balls of green glauconite. Field Collected: Found in large box of uncleaned, untrimmed, Government Pit specimens collected by Leroy Grant of Albany, NH (deceased). Collected in the 1970's. Catalog No.: TBC Notes:
GREIFENSTIENITE Chandlers Mill Mine, Newport, NH 1.7 mm field of view. Broken radial spray of green crystals.	Species: GREIFENSTIENITE Ca₂Be₄(Fe²⁺, Mn)₅(PO₄)₆(OH)₄ · 6H₂O Locality: Chandlers Mill Mine, Newport, NH Specimen Size: 1.7 mm field of view. Broken radial spray of green crystals. Field Collected: Bob Wilken 10/09 Catalog No.: u2234 Notes: A polished grain EDS analysis (BC185) gave a chemistry of Ca_2.15Na_0.65Fe_2.46P₆O_39.8 , normalized for 6 P. Greifensteinite has a Ca:Fe:P ratio of 2:5:6 , so if this is greifensteinite, it is very light on the Fe. Sodium is not part of greifensteinite chemistry, so perhaps it is substituting for some of the calcium. However, greifensteinite is the best fit for the computed chemistry. Greifensteinite has beryllium, which EDS cannot measure. A second polished grain EDS analysis (BC308) gave a chemistry of: Ca_4.06Be_3.81(Fe_5.17,Mn_0.29)_Σ=5.46P₆O_39.8 , normalized for 6 P. The EDS instrument cannot detect beryllium, but my APFU calculator allows entry for very light elements. Here 3.3% Be was added as indicated from the greifensteinite chemistry on webmineral. The BC308 analysis is a quite good match for greifensteinite. Other, better examples, of greifensteinite have been found at the Chandlers Mill Mine.
CALCITE 101 Road Cut, near Shaw Drive, Bedford, NH 4 mm stubby-prismatic crystal	Species: CALCITE Locality: 101 Road Cut, near Shaw Drive, Bedford, NH Specimen Size: 4 mm stubby-prismatic crystal Field Collected: Tom Mortimer 10/21/18 (HBD MJM) Catalog No.: u2218 Notes: A common species, but the only micro crystal one I found at this ledge blasting site.
DRAVITE Winham Mine, Marlow, NH 6 mm field of view	Species: DRAVITE Locality: Winham Mine, Marlow, NH Specimen Size: 6 mm field of view Field Collected: Tom Mortimer 8/18 Catalog No.: u2215 Notes: Collected from coarse-grained pegmatite boulder. Chemical composition computed from atomic percent EDS analysis (BC304) gave: NaMg_0.67Ca_0.06K_0.06Al_5.14Fe_0.09Si_4.13O_44.34 (normalized for one atom of sodium) indicating the sodium dominant tourmaline species dravite. Yes, the Mg + Ca + K total is low for dravite.
CHALCOCITE ? Johnson Rd. Locality, Bow, NH Largest crystal, center, 0.3 mm	Species: CHALCOCITE ? Locality: Johnson Rd. Locality, Bow, NH Specimen Size: Largest crystal, center, 0.3 mm Field Collected: From vein samples collected by Jim Cahoon. Micro found by Tom Mortimer - 10/18 Catalog No.: u2209 Notes: Chalcocite is a best guess based on environment and proximity to some covellite. Chalcocite has not been previously reported from New Hampshire.
PSEUDOLAUEITE Palermo #1 Mine, N. Groton, NH 1.5 mm field of view	Species: PSEUDOLAUEITE Locality: Palermo #1 Mine, N. Groton, NH Specimen Size: 1.5 mm field of view Field Collected: Bob Wilken Catalog No.: A Bob Wilken specimen and photo Notes: Multiple pseudolaueite crystals.
WHITMOREITE Palermo #1 Mine, N. Groton, NH 0.3 mm "navel mine"	Species: WHITMOREITE Locality: Palermo #1 Mine, N. Groton, NH Specimen Size: 0.3 mm "navel mine" Field Collected: Bob Wilken Catalog No.: A Bob Wilken specimen and photo Notes:
WHITMOREITE Palermo #1 Mine, N. Groton, NH 0.3 mm "navel mine"	Species: WHITMOREITE Locality: Palermo #1 Mine, N. Groton, NH Specimen Size: 0.5 mm crystal with strunzite Field Collected: Bob Wilken Catalog No.: A Bob Wilken specimen and photo Notes: [bw] "I can't remember if I have ever seen or found individual whitmoreite crystals like this before. I've seen them on naval mines but not just randomly occurring. I think I would normally have thought of this as jahnsite. Yet the color of these matches the naval mines that are in the same material. Most of them are very small, stubby, poorly formed crystals scattered around."
ARFVEDSONITE Hurricane Mtn., Conway, NH 2 mm crystal blade ARFVEDSONITE Hurricane Mtn., Conway, NH 2 mm crystal blade	Species: ARFVEDSONITE Locality: Hurricane Mtn., Conway, NH Specimen Size: 2 mm crystal blade Field Collected: Leroy Grant - early 1970's Catalog No.: u2223 Notes: Top photo: blade crystal in vug, termination partially obscured. 70 stacked images with Nikon objective. Helicon Method C. Lower photo: 26 stacked images with B&L 5X objective - different orientation. Helicon Method C - a bit grainy.