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Highslide JS
DOLOMITE    Pond Hill, Lisbon, NH
Pair of 1.5 mm dolomite rhombs in talc-like matrix.

Species:           DOLOMITE
Locality:          Pond Hill, Lisbon, NH
Specimen Size: Pair of 1.5 mm dolomite rhombs in talc-like matrix.
Field Collected: Bill Ellis 2009
Catalog No.: u904
Notes: Crystals on side of specimen u104.
Highslide JS
DOLOMITE    Livermore Falls, Campton, NH
7 mm field of view. Milky rhombs of dolomite on quartz to 0.4 mm.

Species:           DOLOMITE
Locality:          Livermore Falls, Campton, NH
Specimen Size: 7 mm field of view. Milky rhombs of dolomite on quartz to 0.4 mm.
Field Collected: Tom Mortimer
Catalog No.: u1118
Notes: Dolomite, CaMg(CO3)2 , indicated by EDS analysis . Low element weight Mg peak somewhat attenuated by EDS detector compared to Fe peak. This would likely be ferroan dolomite, bordering on ankerite.
Highslide JS
DOLOMITE    Livermore Falls, Campton, NH
Zoom view of u1118. Milky rhombs of dolomite to 0.4 mm.

Species:           DOLOMITE
Locality:          Livermore Falls, Campton, NH
Specimen Size: Zoom view of u1118. Milky rhombs of dolomite to 0.4 mm.
Field Collected: Tom Mortimer
Catalog No.: u1118
Notes:
Highslide JS
DOLOMITE    Pike Quarry, Hooksett, NH
0.8 mm pale yellow-tan saddle-shaped dolomite crystals
Species:           DOLOMITE  
Locality:          Pike Quarry, Hooksett, NH
Specimen Size: 0.8 mm pale yellow-tan saddle-shaped dolomite crystals
Field Collected: Tom Mortimer - 10/25/14
Catalog No.: TBC
Notes: A raw crystal on carbon tape EDS analysis (BC24) indicated a Ca, Mg carbonate with minor Fe & Mn. This EDS spectrum suffers from low counts and insufficient averaging. I had difficulty photographing these.
Highslide JS
DOLOMITE - FERROAN   Crushed Stone Quarry, Westmoreland, NH
3 cm specimen of ferroan dolomite crystals

Species:           DOLOMITE - FERROAN
Locality:         Crushed Stone Quarry, Westmoreland, NH
Specimen Size: 3 cm specimen of ferroan dolomite crystals
Field Collected: Tom Mortimer
Catalog No.: 1649
Notes: The initial qualitative EDS analysis of this and similar Westmoreland specimens indicated the ankerite species, Ca(Fe, Mg)(CO3)2. (This EDS detector did not respond to elements lighter than sodium and had a relatively poor Mg response.)
A 2018 quantitative EDS analysis (BC277) indicated insufficient iron (Fe) for this to be ankerite. The indicated chemistry from this analysis was Ca(Mg0.27, Fe0.23)O2.7 , normalized for one atom of Ca. The carbon was not quantified. Thus, Mg dominant over Fe and therefore ferroan dolomite.
A lengthy 2018 discussion on mindat.org mindat.org link indicated that ankerite is quite rare and that most specimens labeled ankerite are actually ferroan dolomite.
Highslide JS
DOLOMITE - FERROAN    Westmoreland Crushed Stone Quarry, Westmoreland, NH
2.5 cm specimen with 6 mm ferroan dolomite crystals on side of milky quartz crystal
Species:           DOLOMITE - FERROAN
Locality:          Westmoreland Crushed Stone Quarry, Westmoreland, NH
Specimen Size: 2.5 cm specimen with 6 mm ferroan dolomite crystals on side of milky quartz crystal
Field Collected: Tom Mortimer
Catalog No.: 673
Notes:
Highslide JS
DOLOMITE - FERROAN    Westmoreland Crushed Stone Quarry, Westmoreland, NH
10 cm specimen with ferroan dolomite crystals to 1 cm
Species:           DOLOMITE - FERROAN
Locality:          Westmoreland Crushed Stone Quarry, Westmoreland, NH
Specimen Size: 10 cm specimen with ferroan dolomite crystals to 1 cm
Field Collected: Tom Mortimer
Catalog No.: 791
Notes:
Highslide JS
DOLOMITE - FERROAN   Crushed Stone Quarry, Westmoreland, NH
1.7 cm specimen

Species:           DOLOMITE - FERROAN
Locality:         Crushed Stone Quarry, Westmoreland, NH
Specimen Size: 1.7 cm specimen
Field Collected: Tom Mortimer
Catalog No.: 532
Notes: Rhombic fracture cleavage clearly evident.
Highslide JS
DOLOMITE - FERROAN  Mine Falls Park, Nashua, NH
Broken 3.5 cm tan rhombic siderite crystal cross-section, with limonite rind, embedded in sphalerite
Species:           DOLOMITE - FERROAN
Locality:          Mine Falls Park, Nashua, NH
Specimen Size: Broken 3.5 cm tan rhombic ferroan dolomite crystal cross-section, with limonite rind, embedded in sphalerite.
Field Collected: Tom Mortimer
Catalog No.:
Notes: Specimen backside is mostly galena.
Ankerite was initially suggested by EDS analysis . A 2018 quantitative EDS analysis (BC278) indicated insufficient iron (Fe) for this to be ankerite. The indicated chemistry from this analysis was Ca(Mg0.51, Fe0.23, Mn0.07)O6 , normalized for one atom of Ca. The carbon was not quantified. Thus, Mg dominant over Fe and therefore ferroan dolomite.