Almandine in Graphite Schist Specimens
At this year’s Tucson shows, the authors saw the breathtaking almandine-pyrope in graphite schist specimens that debuted at the August 2014 East Coast Gem, Mineral, and Fossil Show in Springfield, Massachusetts (figure 1). Mine owner Jason Baskin (Jay’s Minerals, Flemington, New Jersey) first encountered the material from the Red Embers mine (then called the Two Fat Guys mine) in Franklin County, Massachusetts, in the early 2000s, and his family bought the mineral rights to this property in 2008. Mr. Baskin, along with his cousin Kyle Baskin and uncle Kevin Baskin, worked the mine (currently closed to the public) by hand, with tools such as chisels and hammers, for six years before unveiling these specimens and the location of the mine (figure 2).
Good-quality almandine specimens are found in various localities in the eastern United States. This deposit is located in a metamorphosed zone full of layered graphite schist. According to Mr. Baskin, the thickness of the veins can vary from about 1 to 6 feet wide. Black columnar accompanying minerals can be found in the graphite matrix in between the garnet crystals on some specimens (figure 3). This long needle-like mineral was identified as dravite tourmaline. Based on his many years of mining experience at this location, Mr. Baskin says that the garnet crystals tend to have higher quality when they occur within a fold. Some of the garnet crystals are suitable for faceting, but it is the specimens that generate the most purchases. The largest crystal found to date is 28 mm in diameter; the largest faceted stone is 4.7 ct.
These striking specimens displayed sharp, dark red trapezohedra in fine-grained silvery graphitic schist (R.B. Cook, “Almandine New York City, New York County, New York State,” Rocks & Minerals, Vol. 84, No. 3, 2009, pp. 244–252). In a previously published article, Raman spectroscopy identified the garnet as predominantly almandine with some spessartine and minor pyrope components (C. Williams and B. Williams, “Almandine from Erving, Massachusetts,” Journal of Gemmology, Vol. 34, No. 4, 2014, pp. 286–287). Most specimens have multiple garnet crystals embedded in them, with the largest containing more than 100 crystals.
Due to the fine-grained nature of the host rock, a dust mask must be worn during the mining process. The most attractive aspect of these specimens is the exposure of the garnet crystals from both sides of the rock, which allows the light to travel through and make the garnet glow, showing its deep burgundy color (again, see figure 3). To achieve this goal, Baskin has tried numerous abrasives to remove the schist on both sides of the garnet without affecting the crystals’ surfaces. Some of the experimental abrasives included various kinds of glass beads, plastic beads, corn cobs, and even walnut shells. Finally, a special plastic made it possible to expose the garnets from both sides efficiently. The Mineralogical and Geological Museum at Harvard University, the American Museum of Natural History, Yale University, the University of Arizona, and Bill Larson of Pala International all currently own these specimens.
