78 
[Assembly 
NEW-YORK COUNTY. 
Although the number of minerals in this county is comparatively 
large, few of them belong to the class usually denominated useful. 
Carbonate of lime, in various forms, has indeed been found in abun- 
dance. Bog iron ore, and the oxide of manganese also occur, but in 
quantities entirely too small to answer any valuable purpose. 
The following is as complete a list of the minerals of New-York 
island as I have been able to prepare : 
Carbonic acid gas — Given out by a spring in the city. 
Graphite — Several unimportant localities. 
Carbonate of soda — Often formed on damp walls in various parts of 
the city. 
Calcareous spar — Several localities. 
Brown spar — Ditto. 
Dolomite, or magnesi^ii carbonate of lime, generally called marble — 
Several localities. 
Phosphate of lime, crystallized — In dolomite. 
Datholite — In bowlders, which are similar to the rock found at Ber- 
gen-Hill, New- Jersey. 
Quartz, crystallized, limpid and of a rose colour ; also hornstone, jas- 
per, basanite, and fetid quartz — In various parts of the island. 
Serpentine, common and precious — In bowlders in the southern part 
of the island. 
White pyroxene, sometimes in four-sided tables — At the old quarries 
at Kingsbridge, about 208th street. 
Actynolite — In bowlders in the southern part of the island, supposed 
to be from the locality of hydrous anthophyllite. 
Tremolite — At the old marble quarries near 208th street. 
Hydrous anthophyllite — In bowlders on various parts of the island, 
and in places between 10th avenue and the Hudson, and between 57th 
and 63d streets.— (Dr. Gale.f 
Manganesian garnet — At Corker's Hook, {Pierce and Torrey in 
Cleveland) ; also on the shore of the Hudson, between 42d and 50th 
streets. — {Dr. Gale.) 
Kyanite — Found in loose fragments. 
* Report to Mr. Mather— New- York Geological Reports, 1839. 
