Bolton Lime Quarries (Bolton quarry; Whitcomb quarry; Hildreth quarry), Bolton, Worcester Co., Massachusetts, USA

The Bolton locality consists of two limestone (marble) quarries about 1/8 mile apart, and a lime kiln and dumps in between the quarries. John Whitcomb (1712-1785) is believed to have been the first to work the deposit sometime in the 1730s. The north and larger quarry was known as the Whitcomb quarry. The south quarry was called the Hildreth Quarry. The Whitcomb quarry was operated until the 1860s and reopened briefly in 1937 for 2-3 years.

The quarries are in a limestone (marble) unit enclosed in gneiss. According to Emerson (1917): "Where gneiss is in contact with limestone in the quarries at Bolton a layer of black porphyritic diorite 3 or 4 feet thick is commonly next to the limestone. Where this diorite or the fine biotite granite in the gneiss touches the limestone the layer next to it is in some places composed of vein quartz, but ordinarily it is a thick sheet of scapolite rock, in one place 16 feet thick. Next comes a light green pyroxene hornblende layer and next a layer of boltonite [forsterite] limestone grading into the pure phlogopite limestone."

Hansen (1956) provides a good description of the Whitcomb Quarry:
"In 1939, when the marble was being actively quarried and the zonal arrangement was well displayed, G. L. Richmond (unpublished report, 1939) examined the deposit and noted the following general relationships : Next to the gneiss is a scapolite zone that contains chiefly scapolite, quartz, apatite, and sphene. This zone grades into a diopside zone that contains diopside, actinolite, tremolite, apatite, and sphene. A boltonite zone follows containing boltonite, chondrodite, serpentine, and spinel; this zone grades into marble containing phlogopite, allanite, graphite, and garnet. Richmond believes the pegmatite invasion was of two main stages. The first solutions that were introduced, he believes, precipitated quartz-lean biotite-andesine pegmatite and produced diopside, boltonite, and chondrodite by reaction with the marble. Actinolite and tremolite were deposited shortly after diopside. Chlorine later was introduced and through reaction with the andesine produced scapolite. Probably at this time sphene and apatite also formed. Finally, as the solutions weakened and the newly formed contact zones could no longer be penetrated, silica was deposited as vein quartz."

Part of the notoriety of the locality lies not just in its unusual minerals, including what was thought to be a new species, nuttalite. Palache (1923) was one of the best reviewers of the locality and he addressed the problem of typical granite pegmatite minerals reported there: "There is an abundance of coarse granite pegmatite boulders in the immediate neighborhood of the quarry but the rock could not be discovered in place. ... Petalite has long been recorded as occurring at Bolton and Dana gives an analysis of this mineral from there. Many specimens labeled petalite were examined in both collections studied but none of them proved to be correctly identified. They included platy diopside, microcline, scapolite, and especially a fine grained form of partially altered massive scapolite mixed with calcite. It seems probable that the petalite originally found here was from an erratic similar to the spodumene boulder found in Sterling, Massachusetts."

References:
Morse, Jedidiah (1797): The American Gazetteer (Boston: Hall, Thomas, and Andrews).

De Alcedo, Antonio; George Alexander Thompson, Aaron Arrowsmith (1812): The Geographical and Historical Dictionary of America and the West Indies (London: James Carpenter), p. 173.

Meade, William (1823). Localities of minerals (American Journal of Science and Arts, vol. 7, pp. 49-54).

Robinson, Samuel (1825). A Catalogue of American Minerals, With Their Localities, pp. 37-38.

Shepard, C. U. (1832). Boltonite. Treatise on Mineralogy, Part 2, Volume 1, pp 78-79.

Hitchcock, Edward (1835). Report on the Geology, Mineralogy, Botany, and Zoology of Massachusetts, pp. 308-311.

Dana, James Dwight (1839). Supposed new mineral at Bolton, Mass. (American Journal of Science and Arts 35:178-179.)

Jackson, Charles T. (1844). Analysis of Pink Scapolite and Cerium Ochre, from Bolton, Massachusetts. (Boston Journal of Natural History 4:504.)

Jackson, Charles T. (1844). Description and analysis of the pink Scapolite of Bolton, Massachusetts(Proceedings of the Boston Society of Natural History 19:167-168).

Phillips, William; Allan, Robert; Alger, Francis (1844). An Elementary Treatise on Mineralogy, p.418.

Silliman, Benjamin (1849). Descriptions and Analysis of Several American Minerals (Philosophical Magazine and Journal of Science 35:450-465.)

Emerson, B.K. (1917). Geology of Massachusetts and Rhode Island (USGS Bulletin 597)

Palache, C. and Pinger, A. W. (1923). The scapolite deposit of Bolton, Massachusetts (American Mineralogist 8:153-157)

Heinrich, E. W., and Levinson, A. A. (1953). Studies in the mica group; Mineralogy of the rose muscovites (Am. Mineralogist 38:25-49).

Hansen, Wallace R. (1956). Geology and mineral resources of the Hudson and Maynard quadrangles, Massachusetts (USGS Bulletin 1038)

Sherriff, Barbara et al. (2000). Meionite: Rietveld Structure-Refinement 29Si MAS AND 27Al SATRAS NMR Spectroscopy, and Comments on the Marialite-Meionite Series. (Canadian Mineralogist 38:1201-1213).