27 species, 73 mineral photos, 1 unknown, 2 site photos, 3 EDS/XRF analyses. Many photos contributed by Bob Wilken.
A Bob Wilken photo, 2017.
A Bob Wilken photo, 2017.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 9.5 mm apatite crystal.
Field Collected: A former Dana Jewell specimen collected in the early 1980's.
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Photo taken w. a Canon EFS 18-55 kit lens and a 21 mm extension tube combo; a stack of 59 photos w. 70 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 14 mm field of view with close up 0.6 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen
Notes: Mat of bermanite crystals on rockbridgeite/frondelite with blue phosphosiderite. Close up view from stack of 50 images with 6 second diffused light exposurers. Lustrous crystals still have photo flairs.
The Fletcher bermanite is one of its most desireable species.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2 mm field of view. Dark red bermanite on pale blue phosphosiderite
Field Collected: Forrest Fogg, ex. Gordon Jackson, ex. Bob Wilken. A Bob Wilken photo
Catalog No.: u1536
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.2 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1311 on box bottom)
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.2 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1311 on box bottom)
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.2 mm field of view
Field Collected: Dana Jewell
Catalog No.: A Bob Wilken specimen & photo
Notes: Collected by Dana Jewell in the early 1980's.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.8 mm field of view
Field Collected: Dana Jewell
Catalog No.: A Bob Wilken specimen & photo
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.5 mm field of view
Field Collected: Dana Jewell
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] " Looking at the flat-on crystal view under the scope you can barely see them because they are less than paper-thin. It would be nice if light could be thrown all the way to the back of this vug without overexposing the flat ones on the surface level. I don't know what the white blocky forms are. Apatite? "
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2.1 mm field of view
Field Collected: Forrest Fogg
Catalog No.: A Bob Wilken specimen & photo
Notes: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
[bw] Photo taken w. an Amscope Plan 4X; a stack of 66 w. 26 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: Vertical xl pair of childrenite xls ~ 1.4 mm long
Field Collected: Forrest Fogg
Catalog No.: A Bob Wilken specimen & photo
Notes: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 4.5 cm specimen
Field Collected: Clayton Ford
Catalog No.: 2021
Notes: This is the first Fletcher Mine graftonite I have seen.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2.2 cm high specimen
Field Collected: Clayton Ford via Gordon Jackson
Catalog No.: 2101
Notes: My first guess at this cream colored mineral was lithiophilite.
EDS analysis, (BC174 - set 13) indicated a chemistry of (Fe0.77,Mn0.65,Ca0.73)P2O10.5 , normalized for two atoms of P. I forwarded photo and EDS results to Jim Nizamoff and he opined graftonite. Chemically graftonite, (Fe2+,Mn2+,Ca)3(PO4)2 , is a good fit.
The dark mineral between the layers of graftonite is heterosite-purpurite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 8 mm field of view
Field Collected: Bob Whitmore ?
Catalog No.: A Bob Wilken specimen & photo
Notes: A former Pat Barker specimen
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.7 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 8 mm crystal
Field Collected: A purchased specimen - likely collected by Bob Whitmore.
Catalog No.: 1451
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.4 cm crystal
Field Collected: Ralph Lingard
Catalog No.: A Bob Janules specimen and photo
Notes: [bj] These were collected by Ralph Lingard many years ago. He gave them to me. I recalled he had a lot of them in a glass jar.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.5 cm crystal
Field Collected: Ralph Lingard
Catalog No.: A Bob Janules specimen and photo
Notes: [bj] These were collected by Ralph Lingard many years ago. He gave them to me. I recalled he had a lot of them in a glass jar.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.4 cm and 1.5 cm crystals
Field Collected: Ralph Lingard
Catalog No.: A Bob Janules specimen and photo
Notes: [bj] These were collected by Ralph Lingard many years ago. He gave them to me. I recalled he had a lot of them in a glass jar.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2.8 cm specimen
Field Collected: Bob Whitmore
Catalog No.: A Don Swenson collection specimen
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 4.5 mm crystal
Field Collected: Bob Whitmore
Catalog No.: A Don Swenson specimen
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.0 mm jahnsite crystal
Field Collected: Bob Wilken
Catalog No.: A Bob Wilken specimen and photo
Notes: A visual identification by Bob Wilken.A 2.58 mm fov; photo taken w. the Amscope 4X Plan Fluor; a photo stack of 93 w. 15 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2.6 mm field of view
Field Collected: Bob Wilken
Catalog No.: A Bob Wilken specimen and photo
Notes: A visual identification by Bob Wilken.
Photo taken with the Amscope 4X Plan. A photo stack of 93 images with 15 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.4 mm field of view
Field Collected: Bob Wilken
Catalog No.: A Bob Wilken specimen and photo
Notes: A visual identification by Bob Wilken.
Photo taken with the Nikon Plan 10X; a stack of 61 with 15 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.8 mm tall crystal
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u1946
Notes: A visual identification.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.2 mm field of view
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u1950
Notes: A visual identification.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 4 mm field of view. Yellow crystaline matrix is the jahnsite-(CaMnMn).
Field Collected: Clayton Ford, 1960's. Acquired by Gordon Jackson 9/22/03. Gifted to T. Mortimer 3/19/16.
Catalog No.: u1956
Notes: Pale yellow jahnsite-(CaMnMn) with lavender strengite ball and stubby black prisms of rockbridgeite
A polished grain EDS analysis (BC82) indicated a Mn > Fe, Ca, phosphate with a Mn:Fe:Ca:P ratio of about 2.5:1.8:1.1:4 An XRD analysis was attempted on this mineral, but the sample was to small to produce a useful result.
Additional EDS analyses (BC383, A) gave chemistries of (normalized for 4 P):
Ca0.88Mn1.7Fe1.09Al0.44P4F0.49O50
Ca0.84Mn1.73Fe1.04Al0.39P4F0.73O50
Jahnsite-(CaMnMn), {Ca}{Mn2+}{Mn2+2}{Fe3+2}(PO4)4(OH)2·8H2O comes closest to this chemistry.
I have struggled to get a satisfactory identification for this specimen. The aluminum and fluorine observed in the analyses are a bit bothersome. Several mindat.org photos of jahnsite-(CaMnMn) compare favorably with this Fletcher specimen.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes: This jahnsite is more yellow than most from Groton pegmatites. Found in a small vug in rockbridgeite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.2 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes: The Fletcher Mine is the type locality for jahnsite-(CaMnFe). Unknown if this specimen is that specific species.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 3 mm field of view
Field Collected: Clayton Ford
Catalog No.: u1951
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.5 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1303 on box bottom)
Notes: The laueite crystals in this Fletcher lot tended to be short prisms. Many specimens with laueite also had stewartite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.5 mm field of view
Field Collected:
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Photo taken w. a Nikon Plan 10X; a stack of 57 w. 12 um increments.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.5 mm field of view
Field Collected: Brownie Thompson ? and acquired via Pat Barker.
Catalog No.: A Bob Wilken specimen & photo
Notes:
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2 mm field of view. Honey-colored leucophosphite rhombic tablets with powdery white coating.
Field Collected: Bob Whitmore - 1971
Catalog No.: A Bob Whitmore specimen (at time of photo)
Notes: Identification per Bob Whitmore specimen label.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 1.4 mm field of view.
Field Collected: Forrest Fogg
Catalog No.: A Bob Wilken specimen & photo.
Notes: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.1 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes:
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2.3 mm field of view.
Field Collected: Forrest Fogg
Catalog No.: A Bob Wilken specimen & photo.
Notes: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 13 mm field of view
Field Collected: Dana Jewell
Catalog No.: u2592
Notes: Earthy green mitridatite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 3.4 mm field of view
Field Collected: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Catalog No.: A Bob Wilken specimen & photo
Notes: Specimen labeled Mica - muscovite assumed.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.7 mm Paravauxite crystal
Field Collected: Gift from Bob Janules
Catalog No.: u492
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 7 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes: About as nice a NH paravauxite as I have seen.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 3.5 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1239 on box bottom)
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.8 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1239 on box bottom)
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 3.5 mm field of view
Field Collected: Forrest Fogg
Catalog No.: A Bob Wilken specimen & photo
Notes: Rough material col. by Forest Fogg in the 1960's. Acquired from Gordon Jackson in 2016.
[bw] Based on the very irregular fluted crystal forms I believe this is phosphosiderite. I must admit I see nothing but shades of pink phosphosiderite on Mindat although "moss green" is listed for color. Some of the Palermo phosphosiderite trended toward green but certainly not this dark. It's a tiny piece of about 1/8" around so there wasn't much to work with.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 6 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes: Phosphosiderite and strengite both occur as pink to blue to purple balls. They are chemically identical. Visually, they are indistinguishable. Bob's label on this specimen is phosphosiderite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2.5 mm field of view
Field Collected: Bob Janules
Catalog No.: A Bob Janules specimen
Notes: Phosphosiderite and strengite both occur as pink to blue to purple balls. They are chemically identical. Visually, they are indistinguishable. Bob's label on this specimen is phosphosiderite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 8 mm field of view
Field Collected: Clayton Ford
Catalog No.: u1952
Notes: From small box of samples gifted by Gordon Jackson. Some oxide coated milky prisms (apatite?)are present on these pyrite cubes.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 10 mm field of view
Field Collected: Clayton Ford
Catalog No.: u1948
Notes: Embedded rockbridgeite fans.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.4 mm field of view and closer 0.9 mm field of view
Field Collected:
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Looking at the scorodite photo I was inclined to declare this pharmacosiderite because... generally... they look more cubic than anything with sculpted-out edges in most cases. But, then I noticed a mass of flattened xls (the closeup) that have a peak which would be more in line with scorodite. In the upper right corner of this photo there is a composite crystal form that resembles the general shape of a typical scorodite. Anyway, it should be tested.
Top photo taken w. a Nikon Plan 10X objective; a stack of 104 w. 6 um increments.
[tm] Scorodite, an arsenic mineral, is very rare in NH.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2.4 mm long composite siderite crystal mass
Field Collected: Ingeborg Burgraff Jewell in the early 1980's.
Catalog No.: A Bob Wilken specimen & photo
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.9 mm field of view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 1282 on box bottom)
Notes:
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 0.8 mm fov
Field Collected: Clayton Ford. ex. Gordon Jackson
Catalog No.: e.g. u1954
Notes: Not a particularly good photo. Voucher specimen for stewartite at the Fletcher Mine.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 1.2 mm field of view, top photo
Field Collected: Clayton Ford ?
Catalog No.: u959
Notes: Gift from Gordon Jackson. Matt Butler examined some small grains from this specimen with a polarizing microscope and reported: "looking at the pink crushed grains I see interference colors but no noticeable pleochroism so maybe strengite."
A second photo Jan., 2022.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2.8 mm field of view
Field Collected: Inge Jewel
Catalog No.: A Bob Wilken collection specimen
Notes: Bob Wilken identification.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 2.0 mm field of view
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u957
Notes:
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 1.0 mm strengite spheres
Field Collected: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Photo taken w. an EP0 objective; a stack of 75 w. 22 um increments
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 0.35 mm strengite crystal
Field Collected: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Catalog No.: A Bob Wilken specimen & photo
Notes:
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 1.3 mm field of view
Field Collected: Rough material col. by Forest Fogg in the 1960's. Acq from Gordon Jackson in 2016.
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Secondary (?) white strengite on a base of pink crystalline strengite.
Photo taken w. a Nikon Plan 10 X; a stack of 98 w. 14 um increments.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 0.3 mm strengite crystal, top photo.
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u957
Notes: Crystals are in a small vug in rockbridgeite.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 3.6 mm field of view.
Field Collected:
Catalog No.: A Bob Wilken specimen & photo
Notes: [bw] Photo taken w. an EP0 objective; a stack of 85 w. 44 um increments.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 3.3 mm field of view.
Field Collected: Brownie Thompson ?
Catalog No.: A Bob Wilken specimen & photo
Notes: A Brownie Thompson specimen acquired from Pat Barker.
Locality: Fletcher Mine, N. Groton, NH
Specimen Size: 7 mm field of view. Pale green tavorite in rockbridgeite.
Field Collected: Clayton Ford acquired by Gordon Jackson 9/22/03, gifted to Tom Mortimer 2016.
Catalog No.: u2032
Notes: A non-stacked photo. An EDS analysis was consistent with a tavorite identification. Tavorite chemistry is LiFe(PO4)(OH). EDS cannot detect lithium.
Color, fine-grain appearance, and rockbridgeite association are also appropriate for Groton, NH occurrences of tavorite.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 2 cm view
Field Collected: ex Fred Devito collection
Catalog No.: A Doug Rambo specimen (# 2428 on box bottom)
Notes: Green tavorite embedded in rockbridgeite. Not a lot to see here.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 3.3 mm field of view
Field Collected: ex. Pat Barker specimen
Catalog No.: A Bob Wilken specimen & photo
Notes:
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.6 mm field of view
Field Collected: Brownie Thompson and acquired from Pat Barker.
Catalog No.: A Bob Wilken specimen & photo.
Notes: [bw] This "whiteite" may indeed be just a Jahnsite. It's never been tested. It's the tabular form that I tend to associate with whiteite.
Locality: Fletcher Mine, Groton, NH (per label with gifted specimen)
Specimen Size: 2.1 mm field of view
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u1975
Notes: Another whitlockite group on specimen u1975.
During a May, 2022 discussion on these Fletcher Mine whitlockite specimens with Jim Nizamoff, he expressed some reservations about attributing these specimens to the Fletcher Mine. He was not aware of a whitlockite occurrence at Fletcher and opined that the pegmatite chemistry of Fletcher did not well match that needed for whitlockite formation. Jim felt the possibility that these specimens were comingled with Palermo specimens was a strong possibility.
Locality: Fletcher Mine (?), Groton, NH
Specimen Size: 1.4 mm crystal
Field Collected: Clayton Ford. A gift from Gordon Jackson
Catalog No.: u1975
Notes: Chemistry computed from EDS analysis is Ca7.55(Na0.74Mg0.71)P7.0O37 normalized for 7 P. For whitlockite chemistry, Ca9Mg(PO3OH)(PO4)6 . The chemistry of this specimen suggests moderate substitution by Na for Ca and/or Mg.
See locality source caution with above photo.
Locality: Fletcher Mine, Groton, NH
Specimen Size: 1.0 mm field of view
Field Collected:
Catalog No.: u1975
Notes: [bw] "I'm not sure you (tm) want to accept this as whitmoreite. Unfortunately the little hemispheres are so small and somewhat submerged in strunzite. The more prominent xl masses I have labeled as stewartite. I don't think paravauxite usually shows any color. If you get up real close to the little brown ball to the left you can see acicular terminations...tiny as they are.
Photo taken with a Nikon Plan 10X; a stack of 99 with 5 um increments."
Locality: Fletcher Mine, Groton, NH
Specimen Size: 0.9 mm field of view and 0.4 mm field of view
Field Collected: Clayton Ford
Catalog No.: u1949
Notes: From small box of samples gifted by Gordon Jackson.