KEL.l NEW JERSEY. 233 
I rests upon the crystalline rocks (gneisses, schists, etc.) which form 
|e highlands, and is the earliest of the Paleozoic formations in this 
Igion. It varies considerably in composition and in thickness. In 
pray places it is apparently only a coarse and more or less friable 
Indstone, the grains of which are cemented together by lime carbon- 
ic. When fresh its color is steel-blue, but the weathered por- 
[pns are always a rusty brown from the staining of iron oxide. It 
jually, but not always, contains considerable feldspar. In other 
Realities it is a true quartzite, made up of sand grains with siliceous 
Iment. Elsewhere it is a conglomerate, usually of pebbles less than 
i\ inch in diameter, but sometimes containing well-rounded fragments 
■ to 4: inches in size. The pebbles are chiefly of quartz, feldspar, 
ranite, gneiss, and slate; and bits of mica also occur. Locally the 
Inglomerate, where it approaches the gneiss, can be distinguished 
mly with great difficulty from it by the naked eye. It is simply a 
■composed gneiss or granite, slightly reassorted and cemented to 
irm a conglomerate. 
■The thickness of the quartzite varies from a few feet or less to 200 
let or more. Where the rock is thick it is a conglomerate or a coarse 
Ibbly quartzite. Where thinner it is usually a calcareous sandstone, 
lading upward into a limestone, and, perhaps, having near its base 
le or more thin layers of siliceous sandstone or even quartzite. The 
jystaliine foundation on which the quartzite rests was somewhat 
■regular, so that the formation varied greatly in thickness and litho- 
Bgical character, and at the time of its deposition the land lay not far 
1 the southeast of the present outcrop of this rock. 
KITTATINNY MAGNESIAN LIMESTONE. 
iThe quartzite grades upward into a highly magnesian limestone for- 
lation of great thickness. This is commonly called the u blue" lime- 
line to distinguish it from the white, coarsely crystalline limestone 
pund near Franklin Furnace and other localties in Sussex and north- 
Ifn Warren. Its color, however, is not always blue. It is frequently 
fey, sometimes almost white, also drab, or even black. It is fine and 
pen grained. Many of the beds are minutely crystalline, so that the 
jfeshly broken surface has a close resemblance to line-grained lump 
jigar. But it is never coarsely crystalline or marble-like. 
This formation occurs in beds which vary greatly in thickness and 
ipgularity. In part it is made up of thin leaf-like layers of limestone 
jternating with thin sheets of greenish shale. In other beds the lay- 
ps of limestone are an inch or more in thickness, and are separated 
y thinner partings of shale or sandstone. Locally the limestone 
lyers are apparently discontinuous, and the shale or sandy layers not 
ply separate but inclose the more limy^ messes. In great part, how- 
/er, this formation is composed of regular beds, one, two, three, or 
