Oak Street pegmatite, Willimantic, Windham, Windham County, Connecticut, USAi

Regional Level Types
Oak Street pegmatite	Pegmatite
Willimantic	City
Windham	Town
Windham County	County
Connecticut	State
USA	Country

A third beryl which we have investigated is a transparent glassy variety from Willimantic, Ct., with very unusual crystalline habit, which was brought to our notice by Mr. H. N. Bill, of Willimantic, Ct., who collected it from a narrow vein of coarse granite, at an excavation for a roadway on Oak Street, a short distance north of the residence of Mr. Joel Fox. The specimen is irregular in shape, not over 2 1/2 inches in its greatest diameter, it is clear and glassy though much cracked and soiled by infiltrating clay, and with the exception of a small part, where it was broken off, is covered with crystalline facets very irregularly distributed, so that the system of crystallization can not nearly be told. The most prominent face on the specimen is a prismatic face m measuring nearly one square inch in surface, but with irregular contour and deeply pitted by crystalline depressions scattered irregularly over its surface. At either end of this face and for a distance of one half an inch back, the crystal is terminated by a series of dihexagonal pyramids, or berylloids, in parallel position, there being six of them at one end and four at the other; these run into one another in a most confusing manner, while most of the specimen is covered with such a multitude of berylloid and prismatic faces, that their relation to each other can only be made out with difficulty, which is further increased by the somewhat curved and dull nature of the faces, so that they give only poor reflections on the goniometer...

The whole mass has a very much eaten out or etched appearance, and the idea suggests itself that this unusual and curious development, so unlike our ordinary Connecticut beryl, has perhaps resulted from the action of some solvent upon a large mass of beryl.