This specimen is representative of the pyroxene-plagioclase granulites that form from gabbros in the Adirondacks. This famous locality has been discussed, with analyses, by Buddington, 1939, Analysis 64L Table 15, and also in deWaard's 1965 type…
This unique rock contains white crystalline wollastonite, brown grains of andradite garnet, and green diopside. Specimens courtesy of R.R. Bauer, plant manager of NYCO MInes (1980). McLelland reports some grossularite in addition to andradite.
Three hand samples from different facies were collected to represent this sample. Out of two of the largest samples one is a dark fine grained rock while the other is coarse grained. Both contain large (5-8 mm) clusters of biotite.
The Sacandaga Formation consists of a well layered series of dark granulites (AD-12) and leucogneisses (AD-13). Orthopyroxene is generally present in greater quantity than clinopyroxene. It is not known whether these rocks are metasedimentary or…
Relatively coarse facies from the Concord Granite. Thin section contains plagioclase, potassium feldspar, quartz, muscovite, and biotite. Hand sample is a coarse-grained granite with quartz, feldspars, and micas.
The locality near Northville, NY represents the only example of this assemblage that has been encountered to date (1980) in the Adirondacks. The original lithology is that of a typical olivine metagabbro. During granulite facies metamorphism,…
This medium grained facies is one of a number of anorthositic sheets that intrude throughout the stratigraphic section of the southern Adirondacks. A chemical analyses of specimens from this outcrop yield results that are almost identical with…
Spotted Spaulding Granite, member of the Spaulding Quartz Diorite. Part of an irregular sill, not the major facies. Spotted appearance, extends through more mafic facies. Thin section contains quartz, alkali feldspar, plagioclase, mica, and…
This specimen is extremely rich in sillimanite. European geologists refer to such lithologies as "khondolites." This locality is very near some of the old graphite production sites west of Hague.
Thin section shows sillimanite, garnet, k-feldspar.
The predominant lithology of the Peck Lake Formation is a sillimanite-garnet-biotite-quartz-oligoclase gneiss with pods and lenses consisting of two feldspars and quartz (anatectic?). The lithology is widespread throughout the Adirondacks and may…
Granite from the Spaulding Quartz Diorite. Thin section contains plagioclase, biotite, quartz, alkali feldspar, some garnet, and sillimanite. Hand sample shows quartz, feldspars, sillimanite, and mica.