Gloucester, Essex Co., Massachusetts, USA

Area granite quarries and other bedrock exposures of alkaline Cape Ann granite and associated pegmatites and miarolitic cavities.

References:
Cooke, Josiah P., Jr. (1866): On Danalite, a new Mineral Species from the Granite of Rockport, Mass. (American Journal of Science and Arts 47:73-78).

Sears, John Henry (1905): The Physical Geography, Geology, Mineralogy and Paleontology of Essex County.

Palache, Charles (1907): Phenakite as an Alteration Product of Danalite From Gloucester, Mass. (American Journal of Science 24:252-255).

Dennen, W. H. (1992): Bedrock geologic map of the Gloucester and Rockport Quadrangles, Essex County, Massachusetts.