IRON. 
393 
In Connecticut, the crystallized variety of magnetic iron pyrites occurs at Monroe and in 
Trumbull. 
WHITE IRON PYRITES. 
Radiated Sulphuret of Iron, a variety of Iron Pyrites. Cleaveland. — Fer Sulfure Blanc. Hauy. — White Iron 
Pyrites. Phillips and Shepard. — Radiated Pyrites. Thomson. — Prismatic Iron Pyrites. Jameson. — Pris- 
matischer Eisen Kies. Mohs. — Sperkise. Bcudant. 
Description. Colour pale bronze-yellow, sometimes inclining to steel-grey or brass-yellow. 
Fjg 464 Streak greyish black or brownish black. It occurs regularly crystal¬ 
lized ; also stalactitic, reniform and botryoidal. Primary form a right 
rhombic prism. Fig. 464. M on M / 106° 2'. Cleavage parallel with M, 
rather perfect. Fracture uneven. Lustre metallic. Opaque. Brittle. 
Easily frangible. Hardness from 6.0 to 6.5. Specific gravity from 
4.67 to 4.85. Before the blowpipe, the sulphur is driven off, and 
oxide of iron remains. It is sometimes particularly liable to decom¬ 
position. The difference in the crystalline form, however, is a more sure mark of distinction. 
It is only slightly acted on by muriatic acid. 
Varieties. When this mineral occurs in radiated concretions, it is called Radiated Pyrites; 
when it is found in spear-shaped twin or triple crystals, it is named Spear Pyrites; and 
when the crystals are aggregated so as to have the form of the crest or comb of a cock, it 
forms the Cockscomb Pyrites. 
Composition. Iron 45.66, sulphur 54.34 {Hatchett). Iron 45.07, manganese 0.70, sul¬ 
phur 53.35, silica 0.80 ( Berzelius ). The constituents are therefore the same as that of the 
preceding, and it differs from it only in its specific gravity and crystalline form. 
Geological Situation. This mineral is found in rocks similar to those which contain the 
last mentioned species. 
localities. 
Orange County. The crystallized variety occurs two and a half miles southeast of the 
village of Warwick, in a vein of feldspar in granite, associated with zircon and tourmaline. 
The crystals are sometimes an inch in length, of a white and pale bronze-yellow colour, and 
striated longitudinally. They are less hard than those of common iron pyrites, and decompose 
easily. Before the blowpipe, they give out the odour of sulphur, and melt into a globule which 
is black and magnetic when cold. 
Crystals of the form represented 
in Fig. 465 have been found here, 
and also the compound one made 
up of five individuals, Fig. 466. 
M on M' 106° 2'; P on c 160° 
48'; aonc 141° 30'. 
Fig. 465. 
Fig. 466. 
Min. — Part II. 
50 
