114 
GEOLOGICAL REPORT-THIRTY-FIFTH PAR VLLEL. 
No. 86. Between Zuni and the Colorado Chiquito. —Several beautiful pebbles of agate and 
jasper, of different colors, accompanied by specimens of silicified wood. One of the pebbles has 
a deep red color, and is traversed by seams and veins of white quartz. Many of these intersect 
each other in different directions, and produce small faults, one part of the mass being slipped 
by the other. This pebble is susceptible of taking a high polish, and plates cut from it by the 
lapidary show the veins beautifully. 
No. 81. Final Lleno, Gila river, 1851.—This is a small stalactite, obtained on the Gila river 
by Lieutenant AVhipple, in 1851. 
Five or six specimens of sandstone, gypsum, and limestone are without labels, and I have 
not entered or described them. They do not present anything of interest, and one or two appear 
to be fragmentary duplicates. 
ORES AND MINERALS. 
No. 88. Third canon when descending Bill Williams’ forlc. —There are several specimens under 
this number, consisting of rolled or water-worn masses of an epidotic rock, traversed by veins of 
specular iron-ore or Hematite. These veins vary in width from one-quarter to three-quarters of 
an inch, and one of the masses, an inch and a half long, consists entirely of the ore, and has 
been worn until as round as a pebble. The ore is the micaceous variety, and a fractured surface 
presents a brilliant appearance. The scales are radial and plumose, and grouped in rosettes. 
The characteristic red streak and powder is obtained when the mineral is scratched or powdered. 
This ore is composed of iron and oxygen, containing, in 100 parts, iron 70, oxygen 30. It is a 
sesqui-oxide, and crystallizes in rhombohedrons. It is known under a variety of names—as 
hematite, specular iron, iron glance, per-oxide of iron, oligiste iron, &c. It occurs chiefly in 
the granitic or crystalline rocks. The finest crystallizations are brought from the island of 
Elba. The Iron mountain and Pilot Knob, of Missouri, are formed of the same ore. The 
specimens in the collection being transported fragments, the exact locality of the parent 
mass or vein is not known, but it is probably not far from the point where the specimens were 
picked up. 
No. 89. Near Picacho mountain. —This is a small crystalline nodule of the same ore as last 
described, (No. 88,) but this exhibits the planes of the rhombohedron without any modification. 
It is formed of a multitude of crystals, and their points extend outward on all sides. Its com¬ 
position is the same as No. 88—-iron 70, oxygen 30. 
No. 90. Pueblo creek. —Grains of massive specular iron disseminated in granite. The ore, 
however, forms a very considerable part of the mass, and is very friable. It much resembles 
magnetic iron ore, but gives the hematitic streak. 
No. 91. Cerhat mountains, Bill Williams’ fork. —This is a beautiful specimen of fibrous hema¬ 
tite, with long silky fibres extending from several points or centres. The mass is about three 
inches long and one broad, and is pure and free from gangue. The burnishers called blood¬ 
stones, used by jewellers and workers in gold and silver, are made of this variety of hema¬ 
tite, and the specimen in the collection would be suitable for those uses. 
No. 92. Copper ore—New Placer mount, near San Pedro, Neiv Mexico. —There are several 
specimens of copper ore under this number. The gangue appears to be chiefly massive garnet, 
becoming crystalline on the walls of cavities. These crystals are small, but very perfect and 
brilliant. They are rhombic dodecahedrons, with all the edges truncated. Green carbonate of 
copper coats these crystals, and is disseminated through the mass of the specimen. Blue car¬ 
bonate is also present in some of the fissures, and thin crusts of the silicate are also found. 
No. 93. New Placer, San Pedro, Neio Mexico. —These specimens are fragments of a quartz 
vein, and are cellular, porous, and contain cavities lined with crystals. No pyrites or gold can 
be detected by the eye or magnifying glass, but a considerable amount of hydrous peroxide of 
iron (brown hematite) is present. This is probably derived from the gradual decomposition of 
pyrites, which was yery probably auriferous. Mr. Marcou has ticketed the specimen as from 
