A PROCHLORITE BANNERSTONE WORKSHOP

Abstract

O NE and a half miles below the aboriginal workshop on Mt. Johnson Island in the Susquehanna River, described in the October-December, 1921, number of the American Anthropologist, is another bannerstone workshop. This one is located on the east bank of the Susquehanna below Peach Bottom, Lancaster County, Pa. It does not compare in size with the one formerly described, where hundreds of slate bannerstones were shaped; neither was the same material used nor did the same shape of bannerstone prevail. While at the island workshop almost all of the unfinished specimens found were of slate and of the winged type with well-defined centrums; those found at the lower workshop were made of prochlorite and usually of a doubleconvex form truncated at top and bottom or bottom only and without any pronounced centrum. Prochlorite is a soft green stone containing crystals of magnetite. When found in situ it usually occurs contiguous to steatite and is sometimes wrongly called green soapstone. While this material was chosen for making bannerstones, partly because of the ease and safety with which it was worked, the magnetite crystals it contains were a factor that entered into the choice. The shining black crystals added materially to the beauty of the finished bannerstone. The nearest source of this material is about five miles down the river, at Bald Friars, Md. No positively aboriginal prochlorite quarry had thus far been identified here; and it is a question whether the Indian needed to quarry the material since there is such an abundance of it found along a small stream which enters the Susquehanna at this point. However, some of the numerous pits covering the side of Bald Hill may have been made by the Indian in search of prochlorite containing the larger crystals of magnetite. We know from unfinished and broken vessels found that he quarried steatite here