364 Report on national museum, 188G. 



consequence of the magnetic iron it contains, which, though it heightens 

 its beauty, unfits it for exposure to the weather." So far as the present 

 writer is aware these quarries have not been worked since the time 

 mentioned by Professor Shepard ; i. e., since a few years subsequent to 

 1811. 



Delaware. — Serpentine of various shades of green is stated to occur 

 about G miles northeast from Wilmington, New Castle County, and also 

 to the westward, near the State line, where Brandywine Creek enters 

 the State line from Pennsylvania.* So far as the Curator is aware it 

 has never been quarried. 



Maine. — A large bed of serpentine occurs on the northern end of 

 Deer Isle, in Penobscot Bay, in this State. The rock is very massive, 

 and of a dark green, almost black color, sometimes streaked and spotted 

 by veins of amianthus and diallage crystals. It is indeed almost too 

 dark and somber for ornamental work, but seems well adapted for 

 general building purposes and very durable. A company was formed 

 some years ago for working this stone, and who erected a shop for saws 

 and grinding beds. A considerable amount of material was quarried, 

 but the work was soon discontinued, and had not been resumed at the 

 time of the writer's visit in 1884. The company seem to have fallen 

 into the error of supposing that the stone could be used in long pieces 

 and slabs suitable for window trimmings, door-posts, etc., for which, 

 owing to its jointed condition, it is entirely unfitted. The deposit 

 covers a nearly level area of many acres in extent, and within a short 

 distance of the shipping wharf. 



Maryland. — In the vicinity of Broad Creek, in Harford County, in 

 this State, occurs a very large deposit of serpentine, which is described 

 by Professor Genth f substantially as follows : 



" The outcrop of the first or upper bed of green serpentine, of about 

 500 feet in thickness, can be traced by its outcrop almost the whole dis- 

 tance between the upper ford on Broad Creek and over the hill in a north- 

 easterly direction to a ravine on the same creek, a distance of about 

 1,800 feet ; it also crosses the creek in a southwesterly direction, but it 

 has not been ascertained how far it extends. The outcrop of the second 

 bed was measured on the top of the hill between the horseshoe of 

 Broad Creek, and found to be about 180 feet, and it is very conspicuous 

 on the west side of the creek. Its full extent was not determined. The 

 rock is a variety of massive serpentine somewhat resembling williamsite, 

 and shows sometimes a slightly slaty structure. It occurs in various 

 shades, from a pale leek green to a deep blackish green, and from a 

 small admixture of magnetic iron, more or less clouded; rarely with 

 thin veins of dolomite passing through the mass. It is translucent to 

 semi-transparent, exceedingly tough, and its hardness is considerably 



* Geol. of Dela., 1841, p. 35. 

 t Geological Eeport of the Maryland ''Verde Antique" marble, etc., in Harford 

 County, Md., by Prof. P. A. Genth, 1875. 



