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Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA

This page kindly sponsored by Roger Ericksen
 


Detailed Mineral List:
Actinolite
Formula: ☐{Ca2}{Mg4.5-2.5Fe0.5-2.5}(Si8O22)(OH)2
Habit: bladed, acicular, curved aggregates, fibrous
Colour: dark green
Description: Found in bladed and needle-like habits, embedded crystals and massive coarse crystalline aggregates
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94. (Breidenbaugh, 1873) (Januzzi, 1966) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903) (Nightingale 2001)
Photo: © 2011 Harold Moritz . Actinolite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Albite
Formula: Na(AlSi3O8)
Colour: white to cream
Description: Albite is a component of the gneiss wall rock which is abundant at the mine and is also found in massive form and cleavages. Crystals are small and rare
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94. (Januzzi, 1966) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2010 Harold Moritz. Albite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Albite var: Oligoclase
Formula: (Na,Ca)[Al(Si,Al)Si2O8]
Habit: massive
Colour: brown, yellow
Description: Found in brown and yellowish masses
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938).
Allanite-(Ce)
Formula: {CaCe}{Al2Fe2+}(Si2O7)(SiO4)O(OH)
Habit: elongated, tabular
Colour: black
Description: Allanite has been found in relatively large poorly formed crystals in gneiss, also found in thin tabular-like crystals in hornblende. Occurs in very small crystals in scapolite.
Reference: Januzzi, 1966, 1989 Nightingale 2001
Photo: © 2011 Harold Moritz. Allanite-(Ce) from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Almandine
Formula: Fe2+3Al2(SiO4)3
Description: Small crude crystals of almandine are found in gneiss
Reference: (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whit¬lock, 1903).
Amphibole Supergroup
Formula: AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Habit: fibrous
Colour: green
Description: as loose fur-like capillary occurrences
Reference: Jensen (1978) Minerals of New York State, 42-43; Nightingale, 2001
Amphibole Supergroup var: Byssolite
Formula: AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Habit: fibrous
Colour: green
Description: as loose fur-like capillary occurrences
Reference: Jensen (1978) Minerals of New York State, 42-43; Nightingale, 2001
Anhydrite
Formula: CaSO4
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State
Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
Habit: massive
Colour: grey
Description: A gray mass associated with clinochlore and serpentine, and a brown massive form in gneiss was reported Discredited - Winchell - Trainer actually Magnesite
Reference: Jensen (1978) Minerals of New York State, 42-43 (Trainer, 1938, 1941). Nightingale 2001
Antigorite
Formula: Mg3(Si2O5)(OH)4
Habit: massive, also pseudomorphing other minerals
Colour: gray, pale green to gray-green
Description: Serpentine is ubiquitous at Tilly Foster. While early workers tended to refer to serpentine by color, the different colors and habits eventually came to be identified by an extensive, if not cumbersome, assortment of names including: antigorite, bowenite, chrysotile, lizardite, marmolite, picrolite, precious, radiotine, retinalite, and williamsite. Tilly Foster is notable for its abundance and variety of serpentine pseudo-morphs. In addition, massive slickensided serpentine of various colors was readily collected on the dump.
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1939, 1940, 1941) (Whitlock, 1903).
Photo: © 2007 Peter Cristofono. Antigorite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Apophyllite'
Colour: white to colorless
Description: sharp crystals on fracture surfaces in magnetite-serpentine ore. Reported as small white or colorless crystals in gneiss
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94. (Januzzi, 1966, 89) (Manchester, 1931) (Trainer, 1938, 1942) (Whitlock, 1903).
Photo: © Terry Burtzlaff. Apophyllite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Aragonite
Formula: CaCO3
Habit: slender, tapered, radiating groups
Colour: grayish white
Description: Occurs in grayish-white incrustations and as slender, tapered crystals; also radiating groups
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966) (Trainer, 1938).
Photo: © 2011 Harold Moritz . Aragonite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Arsenopyrite
Formula: FeAsS
Habit: flattened twins
Colour: steel grey
Description: Reported to occur in groups of steel gray, flattened, twinned crystals
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966) (Trainer, 1938).
Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
Habit: prismatic, massive
Description: Reported as prismatic crystals and also massive
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Januzzi, 1966, 1989) (Trainer, 1938).
Autunite
Formula: Ca(UO2)2(PO4)2 · 11H2O
Habit: coatings and minute scales
Colour: yellowish
Description: Two occurrences of yellowish coatings and minute scales on gneiss with typical fluorescence have been reported
Reference: Jensen (1978) Minerals of New York State, 42-43 Trainer, 1938, 1942
Axinite-(Fe)
Formula: Ca2Fe2+Al2BSi4O15OH
Habit: axe-head
Colour: colorless, pale brown, plum
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989; Nightingale, 2001
Photo: © 2011 Harold Moritz . Axinite-(Fe) from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Baryte
Formula: BaSO4
Colour: yellow
Description: Small yellow crystals were reported to occur in a cavity in massive chondrodite; also in micro crystals with purple fluorite
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1941).
'Biotite'
Habit: rosettes, cleavable masses
Colour: black, greenish-black
Description: "Rosettes" were reported to occur in lenses and bands of albite in gneiss Large greenish black masses of this mica have been found exhibiting broad cleavage.
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94. Breidenbaugh, 1873; Nightingale 2001
Photo: © 2011 Harold Moritz . Biotite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Bornite
Formula: Cu5FeS4
Habit: compact, massive
Colour: reddish-brown
Description: Reported as compact reddish-brown masses
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989
Brochantite
Formula: Cu4(SO4)(OH)6
Habit: encrustation
Colour: blue-green
Description: Identified as transparent, blue-green micro aggregates
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989
Photo: © 2011 Harold Moritz. Brochantite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Brucite
Formula: Mg(OH)2
Habit: hexagonal tabular or elongated prisms
Colour: pale green, white, grey
Description: Abundant in foliated masses and occasionally found in exceptional crystal groups. Crystallized brucites are Tilly Foster "classics"
Reference: (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2007 Peter Cristofono. Brucite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Brucite var: Nemalite
Formula: Mg(OH)2
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State
Calcite
Formula: CaCO3
Habit: rhombohedral, scalenohedral
Colour: white
Description: Reported as common in massive form but uncommon in crystals. One of the finest scalenohedral crystal groups was purchased by John Trainer and now resides in the Trainer Collection of the New York State Museum, specimen # 13554. Calcite also is present in rhombohedral form. Fluorescent and phosphorescent forms have been reported
Reference: (Bridenbaugh, 1873) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1941, 1942) (Whitlock, 1903).
Photo: © 2011 Harold Moritz . Calcite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Cerussite
Formula: PbCO3
Habit: encrustation
Colour: gray
Fluorescence: yelow-green
Description: With plumbian scheelite in a cavity in altered galena and encrusting the sample
Reference: Matrix, Summer 2001, Tilly Foster edition Januzzi, 1989
Photo: © 2011 Harold Moritz. Cerussite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Chabazite'
Reference: Tschernich, R. (1992): Zeolites of the World, 116
Chalcopyrite
Formula: CuFeS2
Habit: massive
Colour: iridescent
Description: Occurs massive in gneiss; small masses have been reported to be found in pyrrhotite
Reference: (Breidenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938).
Photo: © 2011 Harold Moritz. Chalcopyrite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Chondrodite
Formula: (Mg,Fe2+)5(SiO4)2(F,OH)2
Habit: complex, multi-formed
Colour: Deep wine red, orange, red-brown.
Description: World famous sharp, transparent crystals. The Tilly Foster "signature mineral". In 1873 Bridenbaugh described it "as by far the most interesting species found at this locality" (p. 212). E. S. Dana published two detailed papers on the mineral in 1875. In 1938 Trainer described the chondrodite found here as the "finest mineral from Tilly Foster ... The fine crystals are "antiques" for which you pay fancy prices" (p. 297). The deep red crystals found here are unique in their brilliance, clarity, size, perfection, and variety of forms. Various degrees of serpentinization of these crystals are common. It also was abundant in massive form, and in grains within the magnetite ore. Miners referred to "yellow ore" as magnetite with yellow chondrodite; where the chondrodite was altered to serpentine the ore was referred to as "blue ore"
Reference: Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 214. (Bridenbaugh, 1873) (Dana, 1874) (Dana, 1875, 1875b) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © Christof Schäfer. Chondrodite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O
Description: Minor stains and coatings were reported to have been collected by Ernest Weidhaas in 1931
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989; Trainer, 1938
'Chrysolite'
Description: Reported as abundant although commonly altered to serpentine
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Colony, 1921) (Januzzi, 1966, 1989) (Trainer, 1938).
Chrysotile
Formula: Mg3(Si2O5)(OH)4
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94.
Photo: © Jasun McAvoy & mineralman.com. Chrysotile from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Clinochlore
Formula: Mg5Al(AlSi3O10)(OH)8
Habit: hexagonal, tabular to elongated prisms
Colour: light to dark green, greenish black
Description: Groups of superb dark emerald green crystals, typically "edge-on" on magnetite matrix, are Tilly Foster classics; also a ferroan variety (ripidolite) has been reported. Early workers referred to this mineral as chlorite
Reference: (Bridenbaugh, 1873) (Dana, J. D., 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2011 Harold Moritz . Clinochlore from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Clinochlore var: Leuchtenbergite
Formula: Mg5Al(AlSi3O10)(OH)8
Habit: encrustations
Colour: white
Description: Reported as incrustations and micro-crystals on magnetite - chondrodite matrix also found as white micro-crystals
Reference: (Januzzi, 1966, 1989) (Nightingale 2001)
Clinohumite
Formula: Mg9(SiO4)4F2
Description: Rare, found in highly modified forms
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938).
Clinozoisite
Formula: {Ca2}{Al3}(Si2O7)(SiO4)O(OH)
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State
Danburite
Formula: CaB2Si2O8
Description: An isolated occurrence of small transparent crystals within a cavity in gneiss was reported
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989) (Trainer, 1938).
Datolite
Formula: Ca(HBSiO5)
Description: Pale crystals and masses are reported to have been recovered in gneiss Also occurs with compact radiated natrolite
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1941) (Nightingale, 2001)
Diopside
Formula: CaMgSi2O6
Colour: green, pink
Description: Reported as crystals in pyrrhotite, dolomite, calcite, and gneiss; also in green granular and crystalline masses Also found as stout pink crystals on serpentine and as micro lath-like crystals, transparent, and embedded in a matrix of white calcite.
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Januzzi, 1966, 1989) (Trainer, 1938) (Nightingale 2001)
Photo: © 2011 Harold Moritz . Diopside from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Diopside var: Diallage
Formula: CaMgSi2O6
Reference: Jensen (1978) Minerals of New York State, pp.42-43
Dolomite
Formula: CaMg(CO3)2
Habit: rhombohedral
Colour: white, pale grey
Description: Recovered as large cleavable masses and large rhombohedral crystals. In 1953 Ronald Januzzi supplied a large crystal to the Shell Research and Development Center in Houston Texas, where it was used for research purposes
Reference: (Dana, 1874) (Januzzi, 1966, 1989, pers. comm.) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903). Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 214.
Photo: © Rock Currier. Dolomite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Dravite
Formula: Na(Mg3)Al6(Si6O18)(BO3)3(OH)3(OH)
Reference: Steven C. Chamberlain & George W. Robinson (2013) Collector's Guide to the Minerals of New York State. Schiffer Books.
Photo: © 2011 Harold Moritz . Dravite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Enstatite
Formula: MgSiO3
Habit: massive
Colour: grey-green, grey-brown
Description: Found in large gray-green and gray-brown masses. Exposed faces on dumps commonly alter to a variety referred to as "bronzite"
Reference: (Briden¬baugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2008 JSS. Enstatite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Epidote
Formula: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Habit: elongated, striated prisms
Colour: dark green, yellow-green
Description: Reported as massive in gneiss; dark green crystals up to an inch long are rare.
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1941) (Whitlock, 1903) (Zodac, 1938).
Photo: © 2011 Harold Moritz. Epidote from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Erythrite
Formula: Co3(AsO4)2 · 8H2O
Habit: encrustation
Colour: magenta
Description: Occurs as small (to 1 cm.) globular encrustations mixed with some cobalt rich chlorite (?) as an alteration of linnaeite. Confirmed by EDAX-SEM at the New York State Museum.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989) (Trainer, 1938) (Nightingale 2001)
Photo: © 2011 Harold Moritz. Erythrite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Fayalite-Forsterite Series'
Description: Reported as abundant although commonly altered to serpentine
Reference: Jensen (1978) Minerals of New York State, 42-43 (Colony, 1921) (Januzzi, 1966, 1989) (Trainer, 1938).
Ferro-actinolite
Formula: ☐{Ca2}{Fe2+5}(Si8O22)(OH)2
Reference: Lupulescu, Marian: Rocks& Min. -- May/June 2008
Fluorapatite
Formula: Ca5(PO4)3F
Habit: prismatic
Colour: white, green
Description: Found as small, transparent green crystals; large crude crystals have been reported associated with hornblende. As grayish-white crystals in serpentine; also as an anhedral half inch pale green mass embedded in chondrodite
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Breidenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903) (Nightingale, 2001)
Fluorite
Formula: CaF2
Habit: octahedral, cubic, nearly spherical complexly formed
Colour: purple, white, yellow, pink
Description: First noted by Bridenbaugh in 1873, fluorite from Tilly Foster was described in 1874 by J. D. Dana as occuring "pink, massive, and occasionally in amethystine cubes" (p. 374). It is also found in purple, white and yellow small crystals; the author has noted small spherical aggregates of fluorite in the Trainer Collection of the New York State Museum. Occasionally fluorite is slickensided. Found with crocidolite as pale green octahedral micro crystals in cavities in feldspar.
Reference: (Bridenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1941) (Whitlock, 1903) (Nightingale 2001)
Photo: © 2011 Harold Moritz. Fluorite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Galena
Formula: PbS
Habit: massive
Colour: dark grey,metallic
Description: A coarse granular mass ( 10 cm.) was reported to have been given to John Trainer by a former mine employee
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989
Photo: © 2011 Harold Moritz. Galena from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Goethite
Formula: α-Fe3+O(OH)
Habit: botryoidal
Description: Reported as fibrous with lustrous "patent-leather" botryoidal surfaces, on limonite
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989
Photo: © 2011 Harold Moritz. Goethite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Gold ?
Formula: Au
Description: A single, unconfirmed report of a micro specimen in ore has been reported by a collector
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989) (Nightingale 2001)
Photo: Gold from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Graphite
Formula: C
Description: Found as isolated microscopic flakes in dolomite
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989).
Grossular
Formula: Ca3Al2(SiO4)3
Habit: dodecahedral
Colour: lime green
Description: "Oil-green" dodecahedrons are in the collection of the American Museum of Natural History in New York; also a superb example is contained in the Brush Collection of the Peabody Museum of Natural History at Yale University, specimen # 2. 935.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whit¬lock, 1903).
Photo: © 2011 Harold Moritz. Grossular from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Gypsum
Formula: CaSO4 · 2H2O
Colour: colorless
Description: Small, colorless "lath-like" crystals and crystal aggregates occur in gneiss Also found associated with other sulfates within the ore body.
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938) (Nightingale 2001)
Photo: © 2011 Harold Moritz . Gypsum from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Hedenbergite
Formula: CaFe2+Si2O6
Habit: grains
Description: Round dark grains (variety coccolite) occur in limestone
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989) (Whitlock, 1903).
Hematite
Formula: Fe2O3
Description: Reported as veins in serpentine, and small reddish stains
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Januzzi, 1966, 1989) (Trainer, 1938).
'Heulandite'
Description: Small cleavages and crystals occur in cavities and seams in gneiss
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1939).
Hexahydrite
Formula: MgSO4 · 6H2O
Habit: fibrous masses
Colour: white
Description: Found in micro groups of fibrous white masses
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989
Hisingerite ?
Formula: Fe3+2(Si2O5)(OH)4 · 2H2O
Habit: botryoidal encrustations
Colour: brown
Description: Trainer described botryoidal incrustations of "amorphous brown hydrated ferric-silicate of uncertain composition"
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938).
'Hornblende'
Habit: cleavable masses
Colour: black, green
Description: Occurs in large black and green cleavable masses. Small crystals up to 2 cm. are uncommon; also found in fibrous and acicular crystals
Reference: Jensen (1978) Minerals of New York State, 42-43 (Dana, J. D., 1874) (Januzzi, 1966, 1989) (Trainer, 1938).
Photo: © 2011 Harold Moritz . Hornblende from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Humite
Formula: (Mg,Fe2+)7(SiO4)3(F,OH)2
Description: Found as large, coarse crystals, generally with various degrees of alteration to serpentine, Chukanov(2014) provides the following IR spectrum based on yellow grains: Wavenumbers (cm1): 3560, 3405w, 1075sh, 991s, 954s, 915sh, 888s, 851, 763, 617, 552, 540sh,495sh, 484, 420s, 395s Rruff.info provides the following empirical formula based on microprobe: (Mg0.91Fe0.09)7(Si0.99Ti0.01O4)3(F0.76(OH)0.24)2, see http://rruff.info/humite/display=default/R040071
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903). N.V. Chukanov(2014),Infrared spectra of mineral species: Extended library,Vol 1Springer Geochemistry/Mineralogy of mineral species
Photo: © Rruff Project. Humite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Hydromagnesite ?
Formula: Mg5(CO3)4(OH)2 · 4H2O
Habit: chalky coating
Colour: white
Description: J. D. Dana described a white chalky coating on serpentine
Reference: Jensen (1978) Minerals of New York State, 42-43 Dana, 1874
Hydrotalcite
Formula: Mg6Al2(OH)16[CO3] · 4H2O
Habit: fibrous, foliated
Colour: white
Description: Reported as white and fibrous, sometimes foliated
Reference: (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Ilmenite
Formula: Fe2+TiO3
Habit: flat, tabular, rhombohedral
Description: Flat tabular crystals were found with tourmaline in gneiss Two relatively large crystals, one about 1/4" in diameter, a fine euhedral rhombohedral crystal, embedded in a matrix of magnetite, diopside, chlorite and green serpentine.
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938) (Nightingale 2001)
Ilvaite
Formula: CaFe3+Fe2+2(Si2O7)O(OH)
Reference: Lupulescu, Marian: Rocks& Min. -- May/June 2008
Jarosite
Formula: KFe3+ 3(SO4)2(OH)6
Habit: spheroidal aggregates
Colour: yellow
Description: Observed to occur as small yellow spheroidal ag¬gregates in micro sizes
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989
Kaolinite
Formula: Al2(Si2O5)(OH)4
Description: Reported by Trainer as pseudomorphous after serpentine; six years later he retracted that identification after x-ray analysis
Reference: Jensen (1978) Minerals of New York State, 42-43 Trainer, 1938, 1942
Laumontite
Formula: CaAl2Si4O12 · 4H2O
Habit: elongated prismatic
Colour: white
Description: Groups of white crystals and coatings were reported in gneiss seams
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1941, 1942).
Photo: © 2011 Harold Moritz. Laumontite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Lepidocrocite ?
Formula: γ-Fe3+O(OH)
Habit: encrustations and rosettes
Colour: reddish-brown, blood-red
Description: Found as blood-red incrustations and micro-rosettes on diopside associated with pyrrhotite, pyrite, chalcopyrite, malachite, calcite, aragonite, and amphibole.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989; Nightingale 2001
Photo: © 2011 Harold Moritz. Lepidocrocite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Limonite'
Formula: (Fe,O,OH,H2O)
Reference: Jensen (1978) Minerals of New York State, 42-43
Linarite
Formula: PbCu(SO4)(OH)2
Habit: coating
Description: Micro - incrustation associated with galena, sulfur, cerussite, and plumbian scheelite
Reference: Rocks & Minerals 81:208-213 Januzzi, 1989; Nightingale, 2001
Linnaeite
Formula: Co2+Co3+2S4
Habit: twinned octahedron, cubo-octahedral
Colour: steel-grey
Description: An isolated occurrence of minute, steel-gray twinned octahedral crystals on magnetite was recovered in 1955 Also noted as micro octahedral crystals modified by the cube. Associated with white serpentine and dolomite. As well as magnetite, chondrodite and altered clinochlore.
Reference: Jensen (1978) Minerals of New York State, p.114 (Januzzi, 1966, 1989) (Nightingale 2001)
Photo: © 2011 Harold Moritz. Linnaeite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Lizardite
Formula: Mg3(Si2O5)(OH)4
Habit: massive or as pseudomorphs of various minerals
Colour: white, shades of green
Description: Many specimens of "serpentine" appear to be lizardite based on their softness of about 2.5.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State
Photo: © 2011 Harold Moritz . Lizardite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Magnesite
Formula: MgCO3
Colour: white
Description: Found as small white crystals, in small fine grained marble-like masses (white) as well as in large cleavages
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Nightingale 2001)
Magnetite
Formula: Fe2+Fe3+2O4
Habit: dodecahedral, octahedral, dendritic
Colour: black
Description: Tilly Foster is noted for superb dodecahedral and striated octahedral crystal groups, with individual crystals up to 3 cm. Octahedrons were typically found in seams in gneiss, while dodecahedrons were more commonly found within the magnetite ore body. Dendritic forms on serpentine have also been reported Large masses of this species have been found exhibiting perfect octahedral parting.
Reference: (Dana, 1874) (Januzzi, 1966, 1989) (Man¬chester, 1931) (Trainer, 1938, 1941) (Whitlock, 1903) (Nightingale 2001) Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 214..
Photo: © 2001 John H. Betts. Magnetite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Malachite
Formula: Cu2(CO3)(OH)2
Habit: massive, crusts, stains
Colour: green
Description: Reported as small masses, crusts, and stains
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938).
Photo: © 2011 Harold Moritz. Malachite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Marcasite
Formula: FeS2
Description: Occurrence was first reported by James Manchester, lack of specimens reported since that time is most likely due to rapid decomposition on dumps
Reference: (Januzzi, 1966, 1989) (Manchester, 1931).
Marialite
Formula: Na4Al3Si9O24Cl
Habit: cleavable mass
Colour: white grayish-white, pale pink to lilac
Description: reported as a 5 cm. vein of grayish-white color; cleavage sections show a fibrous appearance
Reference: (Januzzi, 1966, 1989) (Trainer, 1940) (Nightingale 2001)
Photo: © 2011 Harold Moritz . Marialite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Melanterite
Formula: FeSO4 · 7H2O
Habit: cursts and coatings
Description: As an alteration product of an unknown sulfide Thick surface incrustation on hornblende
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989; Nightingale 2001
Microcline
Formula: K(AlSi3O8)
Habit: massive
Colour: flesh
Description: Reported as plentiful in flesh colored masses; orthoclase mentioned in by J. D. Dana in 1874 is most likely microcline
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State (Dana, 1874) (Januzzi, 1966, 1989) (Trainer, 1938).
Photo: © 2011 Harold Moritz. Microcline from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Molybdenite
Formula: MoS2
Habit: foliated, granular
Description: Recovered as small foliated and granular masses; crystals rare
Reference: (Bridenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Habit: cleavable masses, pseudo-hexagonal tabular
Description: Crystal aggregates and books were recovered in gneiss. Some euhedral crystals associated with magnetite and chondrodite. However, the New York State Museum reports that specimens tested turned out to be phlogopite.
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938).
Photo: © 2011 Harold Moritz . Muscovite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Natrolite
Formula: Na2Al2Si3O10 · 2H2O
Habit: acicular, radiating masses
Colour: white
Description: Slender, prismatic crystals and white radiating masses on seams in gneiss
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1942).
Photo: © 2011 Harold Moritz. Natrolite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Olivine'
Description: Reported as abundant although commonly altered to serpentine
Reference: Jensen (1978) Minerals of New York State, 42-43 (Colony, 1921) (Januzzi, 1966, 1989) (Trainer, 1938).
Opal
Formula: SiO2 · nH2O
Habit: coatings
Colour: grayish-white
Description: Occurs as small grayish white coating on various minerals
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938).
Palygorskite
Formula: (Mg,Al)5(Si,Al)8O20(OH)2 · 8H2O
Description: typical fibrous "mountain leather" habit
Reference: Ronald Januzzi collection
Photo: © 2011 Harold Moritz . Palygorskite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Pargasite
Formula: {Na}{Ca2}{Mg4Al}(Al2Si6O22)(OH)2
Reference: Jensen (1978) Minerals of New York State, 42-43
Pectolite
Formula: NaCa2Si3O8(OH)
Habit: radiating fibrous masses
Description: Reported as minute radiating fibrous masses; rare Validation of this species reported many years ago is based upon a serpentine pseudomorph after pectolite found in 1946 (Fredericks) and confirmed. It occurs as a radiated pale green mass 3 x 4" in a pocket in massive chondrodite.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989; Nightingale 2001
Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
Habit: tabular
Description: Plates of crystals occur on serpentine, partially altered to serpentine
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1938)
Photo: © 2011 Harold Moritz . Phlogopite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Posnjakite
Formula: Cu4(SO4)(OH)6 · H2O
Habit: fan shaped aggregates and tabular
Colour: blue-green
Description: Observed as blue-green fan shaped aggregates and single micro crystals on magnetite. Also found as a blue-green tabular micro crystal on serpentine.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989; Nightingale 2001
Prehnite
Formula: Ca2Al2Si3O10(OH)2
Habit: coatings, prismatic
Colour: grayish-green, colorless
Description: Reported as grayish-green coatings on gneiss Also found as perfect, colorless, glassy, prismatic micro crystals on hornblende. Occurs as an encrustation 3" x 4" in surface area (see drawings in Januzzi 1976 pg. 170).
Reference: (Januzzi, 1966, 1976, 1989) (Manchester, 1931) (Trainer, 1938, 1941) (Whitlock, 1903) (Nightingale, 2001)
Photo: © 2011 Harold Moritz . Prehnite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Psilomelane' ?
Habit: spheroidal aggregates
Colour: black
Description: Found as a single occurrence as a black spheroidal micro aggregate in the ore body.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989; Nightingale 2001
Pyrite
Formula: FeS2
Habit: cubic, octahedral
Colour: brassy
Description: Cubes have been found up to .5 cm; also in veins and as coatings Octahedral crystals (micro) have been found.
Reference: (Bridenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903) (Nightingale 2001)
Photo: © 2011 Harold Moritz . Pyrite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Pyroxene Group'
Reference: The Minerals of New York City & Its Environs, New York Mineralogical Club Bull. Vol. 3, No. 1, Manchester, J.G. (1931): 94.
Pyrrhotite
Formula: Fe7S8
Habit: hexagonal prismatic
Colour: brown
Description: Occurs as brown, tabular, hexagonal crystals; more commonly massive
Reference: (Bridenbaugh, 1873) (Dana, 1874) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2015 Harold Moritz. Pyrrhotite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Quartz
Formula: SiO2
Habit: elongated prismatic with rhombohedral terminations
Colour: clear, milky, smoky
Description: Small clear and smoky crystals rare; massive milky quartz is abundant
Reference: (Briden¬baugh, 1873) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938).
Photo: © 2011 Harold Moritz . Quartz from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Quartz var: Rose Quartz
Formula: SiO2
Habit: massive
Colour: pink
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Bridenbaugh, 1873) (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938).
Quartz var: Smoky Quartz
Formula: SiO2
Reference: Jensen (1978) Minerals of New York State, pp.42-43
Photo: © 2011 Harold Moritz . Smoky Quartz from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Riebeckite
Formula: ◻[Na2][Fe2+3Fe3+2]Si8O22(OH)2
Habit: fibrous
Colour: lavender-blue
Description: Variety crocidolite reported as lavender-blue, fibrous masses in gneiss. However, "riebeckite" tested at the New York State Museum from other sites in the Hudson Highlands turned out to be other amphiboles.
Reference: Jensen (1978) Minerals of New York State, 42-43 (Januzzi, 1966, 1989) (Trainer, 1942).
Photo: © 2010 Harold Moritz. Riebeckite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Riebeckite Root Name'
Formula: ◻[Na2][Z2+3Fe3+2]Si8O22(OH,F,Cl)2
Reference: Jensen (1978) Minerals of New York State, 42-43
'Riebeckite Root Name var: Crocidolite'
Formula: ◻[Na2][Z2+3Fe3+2]Si8O22(OH,F,Cl)2
Reference: Jensen (1978) Minerals of New York State, 42-43
Rutile
Formula: TiO2
Habit: acicular
Colour: dark red
Description: As micro specimens on gneiss
Reference: Januzzi, 1989; Nightingale 2001
Photo: © 2010 Harold Moritz. Rutile from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Scheelite
Formula: Ca(WO4)
Habit: bipyramidal
Colour: grayish white, white
Fluorescence: bright bluish white
Description: Several 0.6 cm. X 2.5 cm. veins were found in massive hornblende; also small crystals in galena
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State, p. 278; Januzzi, 1966, 1989
Photo: © 2011 Harold Moritz. Scheelite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Reference: Jensen (1978) Minerals of New York State, pp.42-43
Photo: © Jasun McAvoy & mineralman.com. Serpentine Subgroup from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Serpentine Subgroup var: Marmolite'
Formula: D3[Si2O5](OH)4 D= Mg, Fe, Ni, Mn, Al, Zn
Reference: Jensen (1978) Minerals of New York State, pp.42-43
Photo: © Christopher O'Neill. Marmolite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Serpierite ?
Formula: Ca(Cu,Zn)4(SO4)2(OH)6 · 3H2O
Habit: coatings
Colour: blue-white
Description: Found as tiny tufts of sky-blue acicular micro crystals on white serpentine.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989; Nightingale 2001
Siderite
Formula: FeCO3
Habit: spherical aggregates, cleavable masses
Colour: brown
Description: Reported as brown spherical aggregates on biotite schist, and reddish-brown cleavages
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Januzzi, 1966, 1989) (Trainer, 1939).
Photo: © 2011 Harold Moritz. Siderite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Sphalerite
Formula: ZnS
Colour: yellow-brown
Description: Small masses associated with galena
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State, p. 278; Nightingale, 2001
Photo: © 2011 Harold Moritz . Sphalerite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Spinel
Formula: MgAl2O4
Habit: octahedral
Description: Small octahedral crystals are found with granular chondrodite in limestone
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Januzzi, 1966, 1989) (Koeberlin, 1909) (Trainer, 1938).
Photo: © 2011 Harold Moritz . Spinel from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Stilbite'
Colour: brown
Description: Brown stilbite occurs in gneiss; rare
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2011 Harold Moritz . Stilbite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Sulphur
Formula: S8
Habit: anhedral
Colour: bright yellow
Description: Observed as very tiny micro crystals in cavities in altered galena with scheelite.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State; Januzzi (1989)
Photo: © 2011 Harold Moritz . Sulphur from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Szomolnokite ?
Formula: FeSO4 · H2O
Colour: yellow
Description: Observed in transparent yellow micro crystals. The reference cited was privately published. No validation listed in publication.
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1989
Talc
Formula: Mg3Si4O10(OH)2
Habit: fibrous, foliated, nmassive, pseudomorphous
Colour: pale green, gray-green
Description: Reported as veins in magnetite ore; fibrous and foliated masses have been found in dolomite
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938, 1940).
Photo: © Rob Lavinsky & irocks.com. Talc from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Talc var: Steatite
Formula: Mg3(Si4O10)(OH)2
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State
Thomsonite-Ca
Formula: NaCa2[Al5Si5O20] · 6H2O
Habit: radiating columnar
Colour: white
Description: Reported as white, radiating groups of columnar crystals, on gneiss
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Januzzi, 1966, 1989) (Trainer, 1942).
Thorite ?
Formula: Th(SiO4)
Habit: anhedral
Colour: orange
Description: A single orange, microscopic anhedral mass in hornblende has been reported
Reference: Januzzi (1976) Mineral Localities of Connecticut & Southeastern New York State Januzzi, 1966, 1989
Titanite
Formula: CaTi(SiO4)O
Colour: brown, greenish, yellow
Description: Fine gemmy greenish and yellowish crystals (some twinned) were found in pockets in 1891. Lesser quality brown and yellow crystals, up to 1 cm., have been found in serpentine and albite
Reference: (Januzzi, 1966, 1989) (Manchester, 1931) (Trainer, 1938) (Whitlock, 1903).
Photo: © 2011 Harold Moritz. Titanite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
'Tourmaline'
Formula: A(D3)G6(T6O18)(BO3)3X3Z
Habit: elongated prisms, massive
Colour: black
Description: lustrous black crystals in gneiss and calcite; it also occurs in a brownish clay, and in massive form
Reference: (Januzzi, 1966, 1989) (Man¬chester, 1931) (Trainer, 1938) (Whitlock, 1903).
Tremolite
Formula: ☐{Ca2}{Mg5}(Si8O22)(OH)2
Habit: radiating acicular, massive
Colour: gray-green, gray-blue
Description: Reported as a massive six inch vein four feet in length, gray-blue in color. Peter Zodac reported that Dr. Alonzo Quinn of Brown University confirmed the identification. Also reported to occur in small, radiating groups and flat gray-green crystals on magnetite. Occurs in long grayish-white fibrous tufts in enstatite. As well as in fine and coarse grained aggregates
Reference: (Januzzi, 1966) (Trainer, 1938, 1940) (Zodac, 1938) (Nightingale, 2001)
Photo: © 2011 Harold Moritz . Tremolite from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA
Vermiculite
Formula: Mg0.7(Mg,Fe,Al)6(Si,Al)8O20(OH)4 · 8H2O
Reference: Jensen (1978) Minerals of New York State, pp.42-43
Zircon
Formula: Zr(SiO4)
Habit: elongated prismatic
Colour: brown
Description: Brown crystals up to 3 cm. have been reported in hornblende; also as a constituent of the gneiss country-rock
Reference: Jensen (1978) Minerals of New York State, pp.42-43 (Dana, 1874) (Januzzi, 1966, 1989) (Trainer, 1938).
Photo: © 2011 Harold Moritz. Zircon from Tilly Foster Iron Mine, Brewster, Town of Southeast, Putnam Co., New York, USA

References

Mather, W. W. (1839), Third Annual Report on the Geology of the First Geological District of the State of New York. Albany, New York.

Rogers, H. D. (1840), Final report on the geology of the State of New Jersey. 12-43.

Beck, L. C. (1842), Mineralogy of New York. W. and A. White and J. Visscher, Albany, New York.

Mather, W. W. (1843), Geology of New York, Part I, Comprising Geology of the First Geological District. Albany, New York.

Cook, G. H. (1868), The Geology of New Jersey. Newark, New Jersey.

Breidenbaugh, E. S. (1873), On the minerals found at the Tilly Foster iron mines, N.Y. American Journal of Science: third series: 6: 207-213.

Dana, James D. (1874), On serpentine pseudo-morphs and other kinds from the Tilly Foster iron mine, Putnam County, New York. American Journal of Science, third series: 8: 371-381, 447-459.

Dana, Edward S. (1875), Preliminary notice of chondrodite crystals from the Tilly Foster mine, Brewster, New York. American Journal of Science, third series: 9: 63-64.

Dana, Edward S. (1875b), On the chondrodite from the Tilly Foster mine, Brewster, New York. American Journal of Science, third series: 10: 89-103.

Merrill, F.J.H. and Britton, N.L. (1883), Annual Report of the State Geologist for 1883. 27-77.

Merrill, F.J.H. and Britton, N.L. (1885), Annual Report of the State Geologist for 1885. 36-55.

Wendt, A. F. (1885), The iron mines of Putnam County, N. Y. Transactions of the American Institute of Mining Engineers: 13: 478- 488.

Pelletreau, William (1886), History of Putnam County, New York. W.W. Preston, Philadelphia.

Putnam, B.T. (1886), Report on the mining industries of the United States. Tenth Census, 1880.

Ruttmann, F. S. (1887), Notes on the geology of the Tilly Foster ore-body, Putnam County, New York. Transactions of the American Institute of Mining Engineers: 15: 79- 90

McDowell, F. H. (1889), The reopening of the Tilly Foster iron-mine. Transactions of the American Institute of Mining Engineers: 17: 758-767.

Landis, E. K. (1900), The Tilly Foster mine. The Journal of the Franklin Institute: 150: 223-226.

Whitlock, H. P. (1903), List of New York mineral localities. Bulletin of the New York State Museum: 70: 70-71.

Stewart, A. C. (1908), The magnetite belts of Putnam County, N. Y. The School of Mines Quarterly: 29: 283-294.

Koeberlin, F. R. (1909), The Brewster iron bearing district of New York. Economic Geology: 4: 713-54.

Colony, R. J. (1921), The magnetite iron deposits of southeastern New York. New York State Museum Bulletin: 249-250.

Manchester, J. G. (1931), The Minerals of New York City and its Environs. New York Mineralogical Club, Bulletin: 3(1), New York, NY, 165 p., 127 plates.

Doherty, E. (1934), Report on the Rocks and Minerals Association Second National Outing. Rocks and Minerals: 9(7): 105.

Zodac, Peter. (1934), Club and society notes. Rocks and Minerals: 9(6): 91.

Elwell, Wilbur. (1936), Mineral collecting by hydroplane. Rocks and Minerals: 11(6): 92 -93.

Trainer, John N. (1938), Tilly Foster up-to-date. Rocks and Minerals: 13(10): 291-303.

Zodac, Peter. (1938), Some recent finds at Tilly Foster. Rocks and Minerals: 13(6): 180-181.

Trainer, John N. (1939), Tilly Foster up-to-date. Rocks and Minerals: 14(2): 50-52.

Trainer, John N. (1940), Another year at Tilly Foster. Rocks and Minerals: 15(4): 126–128.

Trainer, John N. (1941), The fifth year at Tilly Foster. Rocks and Minerals: 16(4): 122-126.

Rosch, J. (1942), A Tilly Foster incident. Rocks and Minerals: 17(1): 16-17.

Trainer, John N. (1942), Sixth year at Tilly Foster. Rocks and Minerals: 17(1): 8-9.

Trainer, John N. (1943), More about Tilly Foster. Rocks and Minerals: 18(6): 168-169.

Prucha, John J. (1956), Geology of the Brewster magnetite district of southeastern New York. New York State Museum and Science Service Circular 43.

Bourne, W. (1957), Trip to Tilly Foster, New York. Rocks and Minerals: 32(5-6): 258-260.

Januzzi, Ronald E. (1966), A Field Mineralogy of the Tilly Foster Iron Mine. Mineralogical Press, Danbury, Connecticut.

Sinkankas, John. (1966), Gemstones of North America, Van Nostrand, Princeton, N.J. 675 p.

Frondel, Clifford. (1970), letter to Ronald Januzzi dated January 2 1970, in reference to loss of access to the Tilly Foster mine site.

Nuwer, Henry (1971), The Tilly Foster mine. Rocks and Minerals: 46(3):147-154.

Januzzi, Ronald E. (1976), The Mineral Localities of Connecticut and Southeastern New York State. Mineralogical Press, Danbury, Connecticut.

Januzzi, Ronald E. (1989), Tilly Foster Mineral Chart. Mineralogical Press, Danbury, Connecticut.

Roe, A. (1990), Washington A. Roebling—his life and mineral collection. Mineralogical Record: 21(1): 13-30.

Isachsen, Y. W., Landing, E., Lauber, J. M., Rickard, L. V., and Rogers, W. B., editors. (1991). Geology of New York - A Simplified Account. Educational Leaflet No. 28, Albany, New York.

Tschernich, Rudy. (1992), Zeolites of the World. Geoscience Press, Phoenix, 116.

Januzzi, Ronald E. (1994), Mineral Data Book - Western Connecticut and Environs. Mineralogical Press, Danbury, Connecticut.

Lininger, Jay. (1997), Iron smelting in the Hudson Highlands: a retrospective of the Greenwood Ironworks. Matrix: 5(4): 146-151

Nightingale, Stephen L. (2001a), Mineral Species Reported to Occur at the Tilly Foster Iron Mine. Matrix: 9(2): 73-77.

Nightingale, Stephen L. (2001b), Tilly Foster Pseudomorphs. Matrix: 9(2): 78-79.

Nightingale, Stephen L. (2001c), The Tilly Foster Iron Mine: Southeast, Putnam County, New York. Matrix: 9(2): 51-72.

Smock, J. C. Iron mines and iron-ore districts in the State of New York. Bulletin of the New York State Museum of Natural History: 7: 2223.

External Links

The New York State Museum www.nysam.org/foster/

19th century American Journal of Science search page: http://diva.library.cmu.edu/ajs/search.jsp

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