5S FIELD MUSEUM OF NATURAL HISTORY 
Tlie wall case nearest the copper ores contains foreign zinc 
ores, of which the most important represented in the collection 
are the English and Welsh, the Greek and the Spanish. The 
original “black jack” of the Welsh miners is here represented 
and may be profitably compared with the ordinary yellow and 
brown blendes, which are often miscalled black jack in this 
country. Immediately in front of this case are two floor cases, 
one of German zinc-lead ores, which should be studied in con- 
nection with the German ores of other metals, shown elsewhere. 
The other floor case contains choice examples of the zinc ores 
of Laurium, Greece, which have long been famous for their 
varieties of color and richness of lustre, making them very 
attractive to the eye. They are chiefly the carbonate, smith- 
sonite. 
Additional Spanish zinc ores occupy the bay of another wall 
case, the upper part of which contains the zinc ores of Arkansas. 
The great purity and richness of the American zinc ores as 
compared with the foreign, is at once apparent, even on casual 
inspection, and this high quality will be noted in all the suc- 
ceeding cases which contain American ores. In this case there 
is a collection of the final, intermediate, and by-products of the 
smelting of zinc ores as carried out at La Salle, Illinois. Follow- 
ing the Arkansas ores are two cases of zinc ores from Missouri, 
the principal zinc producing state. Included with these are the 
Kansas ores, which form a continuation of the same deposits. 
With the Missouri ores are shown ores from the similar 
deposits of Wisconsin and western Illinois. These ores appear 
darker than those of Missouri, owing to the enclosure of bitum- 
inous matter. Another visible difference is in the frequent flat 
or tabular form of the Wisconsin ores and the presence of 
larger quantities of sulphides of iron. Large specimens of 
Missouri ores are in an adjacent floor case. 
Following the Missouri zinc ores come those of the south- 
eastern and south-central states. The Virginia and Tennessee 
ores are not essentially different from those of the ordinary type 
of zinc ores, while the deposits of southern Illinois, Kentucky, 
and New Jersey are decidedly unique. 
With the specimens from New Jersey there is a collection 
of those zinc-bearing minerals which occur in sufficient abund- 
ance to be of value as ores. 
