Anthonys Nose, New York A Review of Three Mineral Localities
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Finally, the Catskill aqueduct that supplies the water to New York City from upstate New York was excavated through the area from north to southeast and passed two miles east of Anthonys Nose. Many geologic reports were prepared of the area during the planning and construction of the aqueducts. The aqueduct required excavating deep trenches and long tunnels affording geologists and mineral collectors the opportunity to study the geology.
Above - Geologic map of the Anthonys Nose and Peekskill region (from Berkey and Rice, 1921).
The prominent summits in the Hudson highlands, including Anthonys Nose and nearby Dunderberg are likely cores of eroded anticlines and the surrounding sedimentary and metamorphic rocks are the troughs of synclines. Anthonys Nose is composed of Canada Hill granite, a medium to coarse grained granite. Often this granite has a streaked, foliated appearance due to crudely oriented biotite crystals. Other minerals include microcline and orthoclase feldspars, gray quartz, red-violet garnets and rutile needles. Upon weathering the Canada Hill granite takes on a dull gray appearance with quartz and garnet becoming prominent due to their resistance (Berkey and Rice, 1921). Canada Hill granite has been dated by Potassium-Argon dating to between 800-900 million years old by the Lamont-Doherty Earth Observatory of Columbia University (Schuberth, 1968).
Within the Canada Hill granite are lenticular pods Grenville gneiss that predate the formation. It has been noted that the Canada Hill granite was particularly effective at invading and assimilating the older rocks it invaded. Current theories about the origin of the Canada Hill granite propose that it formed through the granitization of an older rock of similar mineralogy, possibly an arkose sandstone, without ever going through a fluid phase. This process is thought to be the result of the introduction of hot fluids and gases from a deeper magmatic body nearby. (Schuberth, 1968)
Because Canada Hill granite are among the oldest granites in the region, much of the Grenville and Pre-Cambrian faulting has been obscured through rehealing, injection, or recrystallization,. One fault in particular that runs from south-southwest to north-northeast extending from the north end of Iona Island, through two of the mineral locations in this paper is perfectly rehealed and completely crystalline, exhibiting equal strength to surrounding rock. (Berkey and Rice, 1921)
Hudson Railroad Cut Calcite locality, Cortlandt, Westchester County, New York
The calcite coated with drusy quartz that first aroused interest in Anthonys Nose came from the railroad excavations for the New York Central Hudson River Line during the 1840s.
In 1842, no mention of this calcite occurrence was made by Beck in his exhaustive Mineralogy of New York. In the second annual addenda to that book (Beck, 1849) under the mineral discoveries listed for 1848 there is the following entry:
Carbonate of Lime, in six-sided tables obtained in blasting a tunnel for the Hudson Railroad, at Anthonys Nose. This truly magnificent specimen, and almost unique, is presented by John E. Henry, Engineer on the above Road.
At left - Illustration of two calcite specimens from Anthonys Nose from page 88 of Third Annual Report of the Regents of the University (1850) which was compiled by Beck as an addenda to his Mineralogy of New York
This concise report is the first mention found of the calcite occurrence and provides more detail about the occurrence than any subsequent reports in the mineral literature. It pinpoints the discovery to a tunnel on Anthonys Nose, of which there are four. It also gives the discoverer and his position which explains how the specimens were encountered. It can be assumed that the site dates to 1848, as the same article makes no mention of the discovery for the year 1847.
Subsequent reports in the literature add little to this information. The third annual report (Beck, 1850) pictured two specimens with line drawings. Along with the illustrations was the following description of the occurrence:
A novelty in the occurrences of calcareous spar [calcite], is the recent
discovery of groups of crystals in the form of flat, six-sided tables, of
carious sizes, from half an inch to two inches in diameter. These crystals
have been found in the coarse granite near Anthonys Nose, on the Hudson
River, during the excavations for the railroad on the banks of that stream.
The accompanying cuts are drawn from a specimen presented to the State Cabinet
by John E. Henry, which is one of the best I have seen from the locality.
It is more than a foot in length and breadth. I have received several fine
specimens from Mr. Cyrus Fountain, of Peekskill, who has been for several
years actively engaged in collecting minerals of Westchester and Putnam counties;
and to whom I acknowledge myself indebted for many interesting facts, which
he has from time to time communicated.
At right - The original specimen donated by John E. Henry illustrated in Beck (1848) pictured in figure 6. Specimen No. 1597, New York State Museum, Albany, NY. 17 x 8 x 5 cm.
The original specimen illustrated in the line drawings is still in the collection
of the New York State Museum in Albany. Since that time, there are no reports
in the literature of newly excavated specimens, though several books mention
the occurrence, often incorrectly attributing the calcite occurrence to the
Philips Pyrrhotite Mine.
Above left - Display case at the Trailside Museum at the Bear Mountain Zoo. The two large specimens on the bottom row are calcites from the Anthonys Nose railroad excavation. Above right - Detail view of the display at the Trailside Museum showing the drusy quartz overgrowth.
Though calcite specimens from Anthonys Nose are not commonly available through mineral dealers, they are widely represented in private and museum collections. The Smithsonian Institution and American Museum of Natural History both have them in their collections. For those planning a visit to Anthonys Nose, two large specimens can be seen in the geology display at the Trailside Museum located in the Bear Mountain Zoo, located just west of the Bear Mountain Bridge. These specimens were donated from the collection of Williams College.
The specimens on display at the Trailside Museum illustrate two basic types: calcite with drusy quartz overgrowth, and plain calcite crystals. Both show calcite crystals up to two inches across as thin tabular six-sided crystals. Those with the overgrowth of quartz often show a reddish-brown color probably due to iron staining. During visits to the site no visible signs were left inside the tunnels or nearby cuts of the calcite. However nearby in the surrounding bedrock small veins up to six inches wide were observed. It is assumed that the calcite specimens were extracted from pockets within a large calcite vein in the Canada Hill granite. This assumption is supported by the nearby rock dumped to build the railroad bed that likely came from the tunnel excavations. Calcite specimens found in the railroad bed are confined to a short length of the tracks south of the second railroad tunnel. The localized occurrence indicates that these calcites were not imported material, rather the result of blasting the adjacent tunnel.
Current Status and Collecting
The tunnels cut for the New York Central Railroad are directly beneath, and south of, the Bear Mountain Bridge, along the eastern bank of the Hudson River. All tunnels have recently been sprayed with a gunnite-type concrete obscuring the tunnel bedrock from collecting. However the rocks removed during tunnel excavation were used as fill of the railroad bed along the river. Several areas of the railroad bed are scattered with calcite and quartz combinations typical of this locality. However the spectacular specimens of 150 years ago are long gone.
Access to the railroad bed is from two locations only. By parking near the train stop in Manitou, north of the Bear Mountain Bridge, you can hike south along the railroad tracks to the tunnels. However this adds approximately an additional one and one half miles to the hike.
The shorter alternative is to hike down from the eastern end of the Bear Mountain Bridge along a trail used by hikers. Parking is available along both sides of Route 9D, as this is where day-hikers can gain access to the Appalachian Trail. The trail head is on the west side of Route 9D, at the end of the stone wall that extends north from the end of the Bear Mountain Bridge. The trail is steep and slightly overgrown, though the hike is much shorter than the alternative hike along the railroad tracks.
View of the railroad tracks and tunnel along the east side of the Hudson River. Many calcite specimens can still be found in the dumped rock between the tracks and the river edge.
Calcite crystal cluster collected May, 1997 along the railroad tracks south of Bear Mountain Bridge.
Once at the railroad tunnel under the Bear Mountain Bridge, hike south along the tracks. Large Amtrak trains pass through the tunnels at very high speeds from both directions. Do not loiter in the tunnels and keep careful watch for oncoming trains.
Collectors should look on the western side of the tracks, the side closest to the river. Large white calcite crystal clusters and brown drusy quartz can be collected in the rock dumped to build the railroad bed. This is also the safest place to avoid the frequent trains. Often black ash from years of trains passing the site will cover the specimens. The ash can be removed with ultrasonic cleaning.
Considering that 150 years has passed since this locality was first collected, it is surprising to still to find collectible specimens. Though the quality will never match the phenomenal calcites first collected during construction, this location is worthy of additional exploration in the future.
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This locality information is for reference purposes only. You should never attempt to visit any mineral localities listed on this site without written permission of the land owner and/or mineral rights owner and that you follow all safety precautions necessary to protect yourself and the property. Unfortunately, the status of mineral collecting sites change often. Inclusion in this site does not give an individual the right to trespass. ALWAYS ASK PERMISSION prior to entering a collecting location. ALWAYS RESPECT THE PROPERTY OWNER, you are his guest. Never enter a property posted no trespassing. When in doubt, do not enter the property.
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