DEPARTMENT OF GEOLOGY 
59 
The three cases across the entrance to Hall 63 from the zinc 
ores, contain ores of mercury and of various metals and metal- 
loids of lesser importance. 
MERCURY. 
The first case to the right of the entrance from Hall 63 con- 
tains a series of ores bearing mercury and cinnabar, with the 
rocks associated with them, from many localities. Mercury ores 
from Alaska, California, Russia, Mexico, and the United States 
of Colombia, are shown. 
The larger number of specimens represent the well-known 
Spanish mines. A large iron flask, sealed with a leaden seal, 
represents the package in which mercury is ordinarily sold. 
The following case contains additional ores of mercury and 
a series of tungsten ores and chromium ores. 
The third case from the entrance from Hall 63 contains ores 
of metals and metalloids of minor importance. These include 
ores of bismuth, molybdenum and vanadium. The uranium ores 
which also yield radium are placed here as well as the ores of 
the rare earths which yield the materials for the manufacture 
of incandescent gas light mantles. 
Following the ores of the rare earths is a case containing 
ores of arsenic, antimony and aluminum. 
ARSENIC, ANTIMONY AND ALUMINUM. 
Specimens of stibnite, the common antimony ore, are shown 
from various localities in Japan, California, New South Wales, 
United States of Colombia, and Greece. Nearly all these speci- 
ments carry an appreciable percentage of gold. With the stib- 
nites are examples of rarer oxidized ores of antimony, valen- 
tinite, etc. Ingot antimony and products of smelting stibnite 
are also shown. 
Arsenic ores shown here are largely the sulpharsenide of 
iron, leucopyrite. Much of the arsenic of commerce comes as 
a by-product from gold or other ores. One such by-product is 
the arsenical flue dust from treating the silver-lead ores of 
Laurium, Greece, in which distinct crystals of the oxide or 
“white arsenic” are plainly visible. 
This wall case also contains a series of minerals carrying 
