Benchmark Quarry, St. Johnsville, Montgomery County, New York, USA

Glassy smoky skeletal quartz.

© A&M

Clear, doubly terminated quartz crystal with a few black pyrobitumen inclusions.

© Vandall King

A lustrous calcite crystal included with tiny needles of marcasite with dolomite. Specimen size 4.5 x 5 cm.

© A&M

Glassy quartz capped with calcite. Specimen size 5.4 x 1.9 cm.

© A&M

Obtained from Adam Scanlon in 2014, who obtained it from the Bill Hladysz collection in 2011. The Benchmark Quarry is best know as being one of several sites where “Herkimer Diamonds” are found. Though the quarry is not in Herkimer County, it is part of the same formation that yields double terminated quartz in dolostone matrix. At the ...

Large yellow-brown translucent calcite crystal with long, thin marcasite inclusions visible inside the calcite. One of the few calcite crystals I obtained from this locality with no damage. Overall size of mineral specimen: 9x6x4 cm. Size of individual crystals: 7 cm.

© 2001 John H. Betts

This miniature specimen measures 7.4x3.8x3.2cm. The photo is 1.5x1.5cm. Perfect calcite nodules up to 5mm with beautiful exposed marcasite needle clusters up to 4mm surrounded by dolomite all completely covering the dolomitic limestone host. One hardly noticeable, 1.5cm contact area. Collection of Michael J. Lundquist

A large "Herkimer-style" quartz crystal, sharp, lustrous and gemmy, measuring 5 cm, with a smaller crystal nearby, on a matrix that also has sulfides anddolomite, and a cluster of euhedral calcite crystals. Came with a label that shows it to have been purchased at the Rochester Mineralogical Symposium Auction in April of 2000. such a large and ...

© Rob Lavinsky & irocks.com

Marcasite xls in Calcite Specimen: CFB-121 Size: 4.5 x 4 x 2.5 cm Curtis F. Breuer Collection and Photograph

© Curtis F. Breuer

Rhombohedral calcite crystal in a small vug in dolostone. Specimen measures 12 x 8 x 8 cm overall, the calcite crystal measures 2 cm.

© Jay Vonderhey

9.8 x 7.8 x 6.0 cm. Two large, sharp, very glassy, intergrown, doubly terminated Herkimer Diamond quartz crystals highlighted by an interesting plate of gray dolomite rhombs from the less well-known Benchmark Quarry in St. Johnsville, New York. The myriad of internal crazing and rainbow refractions add real character to this striking piece. The ...

© Rob Lavinsky & irocks.com

Herkimer on Dolomite matrix - 6x4x4cm - March of 2013

© Photo & Collection of Martins da Pedra

Herkimer Twin with 4cm - June of 2013

© Photo & Collection of Martins da Pedra

Glassy lustrous quartz included with pyrite. Specimen size 3.2 x 3.5 cm.

© A&M

6.1 x 3.3 x 3.0 cm. A fine, very rare quartz combination from this most obscure Herkimer quartz "diamond" locale, that is not even in Herkimer County. Four striking intergrown, facet-like, water-clear, "diamonds" are artistically set on the front of a tapered pedestal of intergrown smoky quartz crystals (possibly bitumen-included?). The stunning ...

© Rob Lavinsky & irocks.com

Marcasite crystals on Dolomite druse with 5x4x2,5cm - November of 2011

© Photo & Collection of Martins da Pedra

Marcasite with Calcite, Dolomite and Pyrite Golden Marcasite spears included in and protruding from Calcite crystals to 3.5 cm. There is a fully exposed reticulated Marcasite "tree" 7 mm. tall, topped by a .8 mm. Pyrite cube. Various other smaller Pyrite cubes are scattered about, barely visible in the photos. Grey-white Dolomite crystals to 4 ...

© Terry Burtzlaff

A large glassy quartz crystal on matrix with dolomite. Specimen size 7 x 6 cm.

© A&M

Marcasite in Calcite. FOV8.0mm. Nikon D800E / Photar 50mm

© Yaiba Sakaguchi

Close-up view of a rhombohedral calcite crystal in a small vug in dolostone. Field of view is about 6 x 3 cm.

© Jay Vonderhey

A glassy double terminated quartz crystal with dolomite. Specimen size 3.4 x 4 cm.

© A&M

Druse with 6x3x2,5cm - July of 2013

© Photo & Collection of Martins da Pedra

Calcite with Marcasite Size: 5x6cm A Calcite cleavage with the phantom of a previous Calcite rhomb outlined with Marcasite needles.

© Terry Burtzlaff

Micro Marcasite crystals on Dolomite druse with 6x5x2,5cm - June of 2013

© Photo & Collection of Martins da Pedra

Herkimer Quartz on Matrix - Benchmark Quarry, St. Johnsville, Montgomery Co., New York, USA - 110 mm x 70 mm

© Geri Meier

Micro marcasite crystals on dolomite - 6x5x3cm - July of 2013

© Photo & Collection of Martins da Pedra

Two prominent, conjoined calcite crystals from the Benchmark Quarry in St. Johnsville, New York. The back shows a nice association of lustrous, offwhite dolomite crystals. The specimen stands on its own and displays naturally. These calcites strongly resemble Native American hand tools, and ones of this size often fit well in the hand. Upon closer ...

© Paul Stephen Cyr

A glassy lustrous quartz crystal with dolomite. Specimen size 4.8 x 5.5 cm.

© A&M

Quartz on Dolomite with Pyrite and Marcasite Size: 6x7cm "Herkimer Diamond" type Quartz crystals to 4 cm. with included hydrocarbon, on matrix with grey Dolomite crystals to 5 mm. Associated are micro Pyrite and Marcasite crystals. This specimen shows no point of attachment.

© Terry Burtzlaff

Quartz var. Herkimer Diamond with Calcite Size: 6.5x4cm A 6 cm. Herkimer Diamond with 4 translucent Calcite crystals along the top. Minor matrix with small Dolomites, and Marcasite needles on and in the Calcites.

© Terry Burtzlaff

A smoky herkimer diamond perched on a small bit of matrix with dolomite. Specimen size 8.3 x 7.0 cm.

© A&M

Marcasite crystals on dolomite - 20mm view - July of 2013

© Photo & Collection of Martins da Pedra

Marcasite with Calcite, Dolomite and Pyrite Golden Marcasite spears included in and protruding from Calcite crystals to 3.5 cm. Grey-white Dolomite crystals, and Pyrite cubes to .8 mm. completes the assemblage.

© Terry Burtzlaff

Dark stem scepter with herkimer diamond quartz crystals.

© A&M

A very large yellow calcite crystal with an interesting triangular pattern of micro marcasite inclusions, as well as deep cleavage markings. This mine is famous for producing great Herkimer Diamonds, but has also produced interesting calcites with marcasite inclusions. Collected by Dan Irwin and acquired from him. Collection and photo of Hershel ...

© 2015 Hershel Friedman, all rights reserved.

Calcite with Marcasite Size: 3.5x6cm Translucent, pale yellow Calcite crystals to 2.5 cm. on a shard of Dolostone, with minor Dolomite. The Calcites have Marcasite crystals both included, and on the surface.

© Terry Burtzlaff

Calcite w/ Marcasite & Dolomite - Benchmark Quarry, St. Johnsville, Montgomery Co., New York, USA - 10cm across - Blake Barnett Photography - AFMC, Inc. specimen

© Blake Barnett

Micro marcasite crystals on dolomite - 6x5x3cm - July of 2013

© Photo & Collection of Martins da Pedra

Calcite and Quartz on Dolomite Size: 9x11cm Parallel growth Rhombohedral Calcite with Quartz and Dolomite.

© Terry Burtzlaff

18.1 x 13.3 x 11.2 cm. This is a very dramatic specimen of the classic "Herkimer Diamond" quartz crystals from New York. This crystal is 11 x 10 x 7 cm. It looks like carved glass. However, few attain such size and perfection, and still remain on matrix. This is tough rock to mine (generally with hand tools at the legal dig sites), and few matrix ...

© Rob Lavinsky & irocks.com

Smooth but boxy conjoined calcite crystals from the Benchmark Quarry in St. Johnsville, New York. These calcites strongly resemble Native American hand tools, and ones of this size often fit well in the hand. Upon closer inspection, select crystal edges or cleavage planes are outlined with microscopic marcasite crystals of a variety of habits. The ...

© Paul Stephen Cyr

Group with 8x5x4cm - March of 2013

© Photo & Collection of Martins da Pedra

Calcite w/ Marcasite inclusions on Dolomite - Benchmark Quarry, New York - 10.5cm across - Ex. Blake Barnett Calcite Collection - AFMC, Inc. Specimen

© mindat.org

Micro Marcasite crystals on Dolomite druse with 7x5x3cm - March of 2013

© Photo & Collection of Martins da Pedra

Purplish Dolomite crystals with a larger single yellow Calcite crystal that has included Marcasite. There is also a very clear crystal of Quartz next to the Calcite. The Dolomite also has some marcasite druses on it.

© mindat.org

Sample with 6x5x3cm - January of 2012

© Photo & Collection of Martins da Pedra

Marcasite crystals to 1,5mm on Dolomite - January of 2012

© Photo & Collection of Martins da Pedra

Biterminated crystal with 6x3x3cm - January of 2013

© Photo & Collection of Martins da Pedra

Calcite on Quartz Size: 2x3.5cm Two yellowish, translucent Calcite crystals perched on the termination of a broken Herkimer Diamond. The crystal group measures 1.5 cm. across

© Terry Burtzlaff

Marcasite crystals to 1,5mm on Dolomite - January of 2012

© Photo & Collection of Martins da Pedra

4.2 x 3.6 x 3.2 cm. "Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, made dark by small inclusions of anthracite/graphite. The contrast is striking. The larger crystals ...

© Rob Lavinsky & irocks.com

11.4 x 8.8 x 7.8 cm. Lustrous, translucent, large, amber, nail-head calcite rhombs form an imposing large combination piece from this well-known New York quarry. The large frontal rhomb has striking, preferential inclusions of sparkly tiny marcasite crystals that look a Mercedes Benz "star". The limestone matrix is nicely accented with ...

© Rob Lavinsky & irocks.com

Calcite with Marcasite Size: 3.5x6cm Translucent, pale yellow Calcite crystals to 2.5 cm. on a shard of Dolostone, with minor Dolomite. The Calcites have Marcasite crystals both included, and on the surface.

© Terry Burtzlaff

7.3 x 7.0 x 4.8 cm. A fine, large calcite crystal from this well-known New York quarry. The well-formed, very glassy, amber crystal has a beautiful, gemmy termination, like an Elmwood calcite. Ex. Robert Nowakowski Collection.

© Rob Lavinsky & irocks.com

Calcite yellow crystals with white Dolomite crystals and Marcasite. The Calcite fluoresces in a pale color under SW and LW, LW response is shown.

© Mathauser

Crystal with 5x4x3,5cm - June of 2013

© Photo & Collection of Martins da Pedra

"Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, with tiny inclusions of anthracite/graphite that add character and interest. The largest crystal is 1.4 cm, and the contrast ...

© Rob Lavinsky & MineralAuctions.com

Calcite yellow crystals with white Dolomite crystals and Marcasite. The Calcite fluoresces in a pale color under SW and LW, SW response is shown.

© Mathauser

Light brown calcite with marcasite. A pretty large, sharp, flat crystal cluster. Photographed by, and in the collection of Dan Costian.

© Dan Costian

Calcite with marcasite inclusions.

© mindat.org

Black stem sceptered quartz on a thin slice of matrix covered with dolomite.

© A&M

Quartz / Sphalerite / Marcasite Mass: 20g rlh1846

"Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, with tiny inclusions of anthracite/graphite that add character and interest. The largest crystal is 1.4 cm, and the contrast ...

© Rob Lavinsky & MineralAuctions.com

Marcasite crystals with colorless calcite. Collected by Roy LaGrow. Rolf Luetcke specimen and photo.

Lustrous off-white Dolomite crystals with thin blades of slightly iridescent Marcasite from Benchmark Quarry, Montgomery County, New York. The Marcasite measures up to 7 mm in length.

© Kim A Strange

Calcite / Quartz Mass: 43g Ex: Stuart Strife rlh1852

Marcasite crystals with colorless calcite. Collected by Roy LaGrow. Rolf Luetcke specimen and photo.

"Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, with tiny inclusions of anthracite/graphite that add character and interest. The largest crystal is 1.4 cm, and the contrast ...

© Rob Lavinsky & MineralAuctions.com

Lustrous off-white Dolomite crystals with thin blades of slightly iridescent Marcasite from Benchmark Quarry, Montgomery County, New York. The Marcasite measures up to 7 mm in length.

© Kim A Strange

Colorless calcite crystals with marcasite crystals. Collected by Roy LaGrow. Rolf Luetcke specimen and photo.

Single large double terminated Herkimer quartz crystal on matrix, surrounded by Dolomite

"Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, with tiny inclusions of anthracite/graphite that add character and interest. The largest crystal is 1.4 cm, and the contrast ...

© Rob Lavinsky & MineralAuctions.com

"Herkimer Diamonds," famous for their sharp, doubly-terminated form and amazing gemminess, are hard to come by on matrix. Most desirable is the style that we have here: clear, colorless quartz on a matrix of smaller quartz, with tiny inclusions of anthracite/graphite that add character and interest. The largest crystal is 1.4 cm, and the contrast ...

© Rob Lavinsky & MineralAuctions.com

Calcite Xls on matrix. 5 prominent crystals + 1 trying to hide. Beautiful contrast against matrix.

Quartz included with pyrite.

© A&M