Harmotome Ba₂(Si₁₂Al₄)O₃₂·12H₂O
At the center of the image are 3 colorless harmotome crystals. The upper 2 forming at V with the third extend near vertically from the base of the V. To the right is a single harmotome twinned crystal. The other harmotomes are also twinned. The fibrous tan mineral is astrophyllite.
Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada
FOV = 1.38 mm
#1513
NFS

Hematite Fe³⁺₂O₃
On the left side of center are two fractured black hematite crystals. To the right of and below center is a black hematite crystal with off white, unspecified mineral crystals attached.
Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada
FOV = 3.96 mm
#1514
NFS

Hemimorphite Zn²⁺₄Si₂O₇(OH)₂·H₂O₃
Frosty white spheres of hemimorphite on a tan matrix. There is a black patch of an unspecified mineral just above center.
Poudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, Canada
FOV = 3.57 mm
#1515
NFS

Veszelyite, (Cu,Zn)2Zn(PO4)(OH)3·2H2O
Dongchuan District, Kunming, Yunnan, China
FOV = 2.9 mm
#9389
NFS

Cornwallite, Cu5(AsO4)2(OH)4
Agardite-(Y), YCu2+6(AsO4)3(OH)6·3H2O
Green sphere of cornwallite and adjacent mass of cornwallite with agardite-(Y) scattered over the surface.
Falgayrolles, Monteils, Villefranche-de-Rouergue, Aveyron, Occitanie, France.
FOV = 2.6 mm
#9388
NFS

#Calcite can form when cool groundwater warms as it rises to the surface. Calcium carbonate exhibits inverse solubility -it's less soluble in warmer water. As a result #tufa deposits can form -like those at Mono Lake. A nice write up of groundwater carbonate deposits at:
ontariobeneathourfeet.com/flow
#MinCup23 #Ontario #Carbonate #MineralSprings

In this marble, #calcite has replaced the #aragonite that was in the rock at high pressures during subduction but has retained the shape of the aragonite columns. #MinCup23

#calcite that was formerly #aragonite columns and then partly recrystallized. Crossed polarized light images of thin sections. #MinCup23

Today's mineral I'm voting for in #mincup23 is #calcite. No surprise, since many clams make their shells from it! But calcite is a very versatile mineral. All these are calcite (Natural History Museum Vienna and Smithsonian) mineralcup.org/2023/campaigns/

Tyrolite, Ca2Cu9(AsO4)4(CO3)(OH)8·11H2O
Azurite, Cu3(CO3)2(OH)2
Blue green tyrolite with azurite.
La Amorosa mine, San Rafael claim, Villahermosa del Rio, Castellón, Valencian Community, Spain
FOV = 3.5 mm
#9391
NFS

Kasolite, Pb(UO2)(SiO4)·H2O
Clusters of yellow kasolite crystals.
San Rafael Mine, Cardeña, Córdoba, Andalusia, Spain
FOV = 1.8 mm
#9392
NFS

Hubeite, Ca2Mn2+Fe3+Si4O12(OH)·2H2O
Manganbabingtonite, Ca2Mn2+Fe3+Si5O14(OH)
Fengjiashan Mine, Daye Co., Huangshi, Hubei, China
Reddish brown hubeite with dark manganbabingtonite on quartz.
FOV = 0.9 mm
#9393
NFS

Fluoro-edenite, NaCa2Mg5(Si7Al)O22F2
Multiple fluoro-edenite crystals associated with tridymite and a feldspar group mineral.
Harter Mountain, Linn County, Oregon, USA
FOV = 3.6 mm
#9397
NFS

Enstatite, Mg2Si2O6
Fluorapatite, Ca5(PO4)3F
Several brown enstatite crystals with colorless needles of fluorapatite.
The steep terminations of the enstatite distinguish from the fluoro-edenite found here.
ID based on comparison to analyzed material from similar Oregon localities.
FOV = 1.4 mm
#9398
NFS

Fluoro-edenite, NaCa2Mg5(Si7Al)O22F2
Several yellowish brown fluoro-edenite crystals. They can be distinguished from enstatite by the flatter crystal termination.
ID based on comparison to similar analyzed material from similar Oregon localities.
Harter Mountain, Linn County, Oregon, USA
FOV = 1.7 mm
#9399
NFS

Augite, (Ca,Mg,Fe)2Si2O6
Enstatite, Mg2Si2O6
Fluorapatite, Ca5(PO4)3F
Tridymite, SiO2
Light olive green augite at center with and enstatite crystal extending down from the lower right corner. There are several elongated colorless fluorapatite crystals visible. Numerous pseudohexagonal tridymite crystals are scatter across the specimen.
Harter Mountain, Linn County, Oregon, USA
FOV = 1.1 mm
#9400
NFS

Offretite, KCaMg(Si13Al5)O36·15H2O
Mont Semiol, Châtelneuf, Montbrison, Loire, Auvergne-Rhône-Alpes, France
FOV = 1.0 mm
#9497
NFS

Phillipsite Series
Mailhac quarry, Saint-Jean-le-Centenier, Largentière, Ardèche, Auvergne-Rhône-Alpes, France
FOV = 1.0 mm
#9498
NFS

Clinoclase, Cu3(AsO4)(OH)3
Dark blue rectangular clinoclase crystals with an unspecified bluish green mineral.
Olmet-et-Villecun, Lodève, Hérault, Occitanie, France
FOV = 1.6 mm
#9499
NFS

Duftite, PbCu(AsO4)(OH)
Chrysocolla, (Cu2-xAlx)H2-xSi2O5(OH)4·nH2O
Duftite, PbCu(AsO4)(OH)
Hemimorphite, Zn4(Si2O7)(OH)2·H2O
Green spheres of duftite on blue chrysocolla with colorless blades of hemimorphite.
3 Metals Mine, Weepah Mining District, Esmeralda County, Nevada, USA
FOV = 3.0 mm
#9501
NFS

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