BUILDING AND ORNAMENTAL STONES. • 419 



but the attention of capitalists being thereby called to the extent of the 

 granite ledges in this vicinity other works were soon established, and 

 at the present time the two towns of Qnincy and West Qaincy contain 

 upwards of thirty quarries. Altogether these produce not less than 

 700,000 cubic feet annually, and give employment to upwards of eight 

 hundred men. 



The Qaincy granites are as a rule dark blue-gray in color, coarse 

 grained, and hard. A pinkish variety is quarried to a slight extent. 

 They are all hornblende granites, and their general appearance so char- 

 acteristic that once seen they are always easily recognizable wherever 

 met with. As already mentioned these rocks contain besides hornblende 

 a very brittle variety of pyroxene, which makes the production of a per- 

 fect surface somewhat difficult. Nevertheless, they are very exten- 

 sively used both for rough and finished work. The United States 

 custom-houses at Boston, Mass., Providence, E. I., Mobile, Ala., Sa- 

 vannah, Ga<, New Orleans, La., and San Francisco, Cal., are of this 

 stone, as are also the new Masonic Temple and Eidgeway Library build- 

 ing, in Philadelphia. In Boston alone there are one hundred and six- 

 ty-two buildings constructed wholly or in part of this material. Its 

 suitability for interior decorative work can not be better shown than 

 by reference to the polished stairways and pilasters in the new city 

 buildings at Philadelphia. 



Other very extensive quarries of hornblende-granite are located at 

 Cape Ann, in the town of Gloucester, where it is stated * that quarry- 

 ing was commenced as early as 1824 by a Mr. Bates, of Quincy. The 

 largest quarries in the State, and, with the exception of those at Viual- 

 haven, Me., the largest works now in operation in the United States, 

 are situated at this place. Like that of Quincy the rock is hornblendic, 

 though frequently considerable black mica is present.! The texture is 

 coarse and the color greenish, owing to the orthoclase it contains. Some 

 varieties are, however, simply gray. It is a hard, tough rock, eminently 

 durable, and well suited for all manner of general building and orna- 

 mental work. The stone has been used in the construction of the post- 

 office and several churches and private buildings in Boston, and the 

 Butler house on Capitol Hill at Washington. 



Other hornblendic granites, somewhat similar in appearance, are quar- 

 ried at Eockport, Peabody, Wyoma, Lynn, and Lynnfield, all of which 

 are represented in the Museum collection. The Eockport stone is the 

 most important of these, and has been quarried since 1830. [n color 

 and texture it is indistinguishable from much of the Gloucester stone, 

 but, if anything, is of a more decided greenish hue. In the quarries 

 it is extremely massive, and blocks 100 feet long by 50 feet wide and 10 



* History of Gloucester, Cape Ann, by J. J. Babson, p. 577. 



tTho black mica of the Gloucester and Rockport granites Las been shown by Pro. 

 fessors Dana and Cooke to be lepidomelaue or anuite. (Text book of Mineralogy, p. 

 313). 



