188 NEW YORK STATE MUSEUM 



and in Clayton, Jefferson county. In parts of Clinton county the 

 stone is too friable for building. 



The most extensive openings are near Potsdam; the stone 

 is hard, compact and even-grained, and pink to red in color. 

 Some of it has a laminated structure and striped appearance. It 

 is an excellent building stone and is widely known and esteemed 

 for its beauty and durability. 



The Hammond quarries produce a gray to red stone. Nearly 

 all of the output is cut into paving blocks and street material. 



Hudson river sandstone 



Rocks of this group outcrop in Orange county, northwest 

 of the Highlands and in the valley of the Hudson river north- 

 ward to the Champlain valley in Washington county. From the 

 Hudson westward, the Mohawk valley is partly occupied by them. 

 The belt increases thence in breadth, in a northwest course across 

 Oneida, Oswego and Lewis counties, and continues to Lake 



Ontario. • •■ 



The rocks consist of shales interbedded with sandstones and 



silicious conglomerates. 



The sandstones are generally fine-grained and of light-gray or 

 greenish-gray color. They are often argillaceous and not adapted 

 for building purposes. But the even-bedded and well-marked 

 jointed structure makes the quarrying comparatively easy, and 

 the nearness to lines of transportation, and to the cities of the 

 Hudson and Mohawk valleys have stimulated the opening of 

 quarries at many points. 



For common rubble work and for local use, the quarries in this 

 formation have furnished a large amount of stone. The more 

 important quarrying centers are now at Rhinecliff-on-the-Hudson, 

 New Baltimore and Troy, in the Hudson valley; at Aqueduct, 

 Schenectady and Duanesburg, Schenectady county; and Frank- 

 fort Hill, Oneida county. Flagstones are quarried from this 

 formation in the gorge of the Bozenkill a few miles northwest 

 of Altamont, Albany county. 



