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Iconic Specimens Doubtless, these large almandine garnets will become known as classics, similar to the almandine crystals from Russell, Massachusetts. Large, sharply formed almandine crystals from Mt. Marie were first recovered in May 2017. The pegmatite units, exposed between overburden-concealed areas, are sufficiently discontinuous to prevent determining whether the mountain crest is one pegmatite or a swarm of several pegmatites. These garnets are late crystallization products, which formed near the end stage of the primary pegmatite crystallization, as indicated by the crystals' location in contact with quartz core segments, which usually (but not always) is the last crystallized part of the pegmatite (London [13]; Roering [16]). [Extracted from the article]

Cathodoluminescence (CL) measurements from a few single crystals and fragments of Pulsifer apatite in general showed areas of bright yellow-green CL emission corresponding to pale purple or white parts of the apatite. Purple apatite is a rare variety of fluorapatite that is widely distributed in many rock types. Description of the Roebling Apatite The Roebling apatite is considered by many mineral collectors to be one of the finest specimens of fluorapatite ever discovered. The best purple apatite specimens were mined from the Pulsifer quarry and include the world-famous Roebling apatite, which currently resides in the mineral collection of the National Museum of Natural History, Smithsonian Institution (fig. 1). [Extracted from the article]

The Emmons pegmatite, noted for its many phosphates, is Maine's most species-rich pegmatite. The Emmons pegmatite (fig. 1) is an example of a highly evolved boron-lithium-cesium-tantalum-enriched pegmatite. The Emmons pegmatite, one of Maine's major micromineral locations, is not the only pegmatite on Uncle Tom Mountain: the highly evolved Dumper Dew pegmatite ([29]) and the larger but less evolved Tiger Bill pegmatite are two of the other pegmatites. In the Emmons pegmatite, "biotite" occurs only in the wall zone as platy to elongated crystals to 8 cm. This mode of occurrence is typical for more evolved pegmatites worldwide. The Emmons pegmatite is a highly evolved boron-lithium-cesium-tantalum-enriched pegmatite formed by anatexis of migmatites ([27]; [31]) as a result of postorogenic, prerifting extension and decompressional melting about 250 Ma. [Extracted from the article]