IRON. 
401 
Dr. Thomson remarks, that the reason of the difference in the results of Vauquelin, Lau- 
gier, Klaproth, Seybert and Berthier, is that they did not employ pure specimens. He denies 
that silica is essential to the mineral, as has been asserted by Berthier and others. 
Geological Situation. This mineral occurs in beds, veins and detached grains or crystals, 
in serpentine, porphyry and trap rocks. In this State, it is found only in small quantities in 
the beds of serpentine, and of the allied minerals. 
Uses. Chrome-iron ore is employed in the manufacture of the chromates, some of which 
are highly esteemed and largely used as paints. 
LOCALITIES. 
Putnam County. Crystals of chrome-iron ore are occasionally met with in the serpentine 
and magnesian carbonate of lime at Hustis’ farm in Phillipstown. A crystal has been obtained 
here, with the base a quarter of an inch in diameter. It resembles black spinelle, but its 
powder is attracted by the magnet, and its blowpipe characters agree with those just noticed. 
Minute grains or crystals of the same mineral have also been found in the vicinity of 
Carmel, in this county. 
Orange County. Minute octahedrons of chrome ore are found in a talcy mineral accom¬ 
panying a bed of magnetic iron ore, at the Wilks mine in the town of Monroe. 
Richmond County. Octahedral crystals of this mineral have long 
been credited to the serpentine at the Quarantine and elsewhere in this 
county. It is probable that they have sometimes been nothing more 
than magnetic iron ore. 
Westchester County. The serpentine near Rye and New-Ro- 
chelle, contains black metallic grains, which are supposed to be chrome 
iron ore. 
Fig. 476 represents a modified octahedron of this mineral, found 
at Hoboken in New-Jersey {Shepard.) 
Fig. 476. 
VIVIANITE. 
Fer Phosphate. Hauy. — Phosphate of Iron. Cleaveland and Phillips. — Vivianite. Thomson and Shepard. — 
Prismatic Blue Iron. Jameson. — Dichromatisches Euklas-Haloid. Mohs. 
Fig. 477. 
Description. Colour varying from pale green to indigo- 
blue. Streak bluish white, but on exposure changing to in¬ 
digo blue. It occurs regularly crystallized; also massive, 
disseminated, and in thin coats. Primary form a right oblique 
angled prism. Fig. 477. M on T 125° 18k Cleavage per¬ 
fect parallel to P. Lustre pearly, inclining to metallic, on P ; 
on the other faces, vitreous. Varies from transparent to 
opaque. Hardness from 1.5 to 2.0. Specific gravity 2.66. 
51 
Min. — Part II. 
