IRON. 185 
crystals have been found at Imlaystown, N. J. At Allentown, 
Monmouth County, and Mullica Hill, Gloucester County, N. 
J., are other localities. It often fills the interior of certain 
fossils. Occurs also at Harlem, N. Y., in Somerset and 
Worcester counties, Md., and with bog ore in Stafford 
County, Va. Abundant at Vandreuil in Canada, where it 
is associated with limonite. 
The blue iron earth is an earthy variety, containing about 30 per 
cent. of phosphoric acid. 
Ludlamite. A clear green hydrous phcspbate of iron in monoclinic 
crystals ; from Cornwall. 
Dufrenite. A hydrous phosphate of iron sesquioxide. It hasa dull 
green color, and is often found in radiated forms. 
Cacoxenite. Occurs in radiated silky tufts of a yellow or yellow- 
ish-brown color. H.=8-4. G.—3°88. It is a phosphate of iron 
sesquioxide, and often contains alumina. It differs from wavellite, 
which it resembles, in its more yellow color and iron reactions. It 
also resembles carpholite, but has a deeper color, and does not give 
the manganese reactions. It occurs on brown iron ore in Bohemia, 
Chalcosiderite and Andrewsite are other iron phosphates. 
Strengite. A hydrous iron phosphate related in formula to scoro- 
dite. From near Giessen. 
Arsenates of Iron. 
Pharmacosiderite, or Cube ore. Occurs in cubes of dark grcen to 
brown and red colors. Lustre adamantine, not very distinct. Streak 
greenish or brownish. H.=2°5. G.=—8. It is a hydrous arsenate of 
iron sesquiozside, containing 43 per cent. of arsenic pentoxide. From 
the Cornwall mines ; also from France and Saxony. 
Scorodite. Crystallizes in rhombic prisms, with an angle of 120° 10’ 
between its secondary prismatic planes. Color pale leek-green or liver 
brown. Streak uncolored. Lustre vitreous to subadamantine. Sub- 
transparent to nearly opaque. H.=3°5-4. G.=3-1-3°3. A hydrous 
arsenate of iron sesquioxide, containing 50 per cent. of arsenic pen- 
toxide. From Saxony, Carinthia, Cornwall, and Brazil; and minute 
crystals near Edenville, N. Y., with arsenical pyrites. The name of 
this species is from the Greek skorodon, garlic, alluding to the odor 
before the blowpipe. ron sinter is an amorphous form of the same 
mineral. : 
Arseniosiderite is another iron arsenate. 
Siderite.— Spathic Iron. Iron Carbonate. 
Rhombohedral. In rhombohedrons with easy cleavage 
parallel to a rhombohedron of 107°. Faces often 
curved. Usually massive, with a foliated struc- _ 
ture, somewhat curving. Sometimes in globular 
concretions or implanted globules. 3 
Color light grayish to brown; often dark 
brownisu-red. It Lecomes nearly black on cx- 

