DEPARTMENT OF GEOLOGY 31 
large wine-colored calcites from Joplin, Missouri, with still 
larger ones of violet color from the same region. Other remark- 
able specimens of carbonates in the wall cases include blue smith- 
sonite from Greece, aragonite from Sicily, and azurite and mala- 
chite from Arizona. In the floor cases containing carbonates, 
smaller specimens of calcites are shown, most of which are re- 
markable for their brilliancy and perfection. The rhodochrosites 
from Colorado are of rare beauty of color. The series of cerus- 
sites is excellent, and some remarkable azurites and malachites 
are shown. The series of silicates begins with the feldspars and 
is then followed by pyroxenes and amphiboles. A series of beryls 
following includes emeralds, aquamarines and other gem stones. 
The varieties and localities of garnet are next displayed and next 
a superb series of phenacite, dioptase and topaz. Tourmaline is 
fully represented, the best specimens being from Maine, Cali- 
fornia, and the Island of Elba. Then follow the zeolites, a group 
of hydrous silicates named from their easy fusibility before the 
blowpipe. The specimens in the adjoining wall cases contain a 
remarkable series of the richly colored amazon-stones of Colo- 
rado, garnets of large size and various coloring, large crystals of 
beryl, a mass of lapis-lazuli weighing about 200 pounds, a 
splendid group of epidote from Alaska, and large and fine speci- 
mens of tourmaline. Passing to Hall 64, the first wall case at 
the left contains a complete series of the varieties of mica, fol- 
lowing which are the hydrous micas, the serpentines, talcs and 
clays, and the minerals containing the rarer elements, such as co- 
lumbite, samarskite, etc. Following these in the wall cases on the 
north side of the hall are the phosphates, arsenates, borates, 
uranates and sulphates. Among these the vanadinites from 
Arizona, and olivenites, conichalcites and tyrolites from Utah, 
are of exceptional beauty and rarity. The turquoises from Ari- 
zona, autunites from South Dakota, barites from England and 
anglesites from Utah are also noteworthy. The systematic col- 
lection terminates in the wall cases on the east wall in the last 
case, especially noteworthy being the specimens of wulfenite 
from Arizona, amber from Prussia and jet from England. A 
collection of pseudomorphs illustrates how one mineral may be 
replaced by another. Then is exhibited a collection of radio- 
active minerals with photographs made by the specimens them- 
selves. Large gold nuggets found in Australia and California 
