1244 MINERALS YEARBOOK, 1941

GEOGRAPHIC DISTRIBUTION OP PLANTS

 Figure 3 shows the location of quarnes in the Umted States pro. ducing concrete
aggregate and road stone. Limestone quarries abound in the Appalachian Mountain
area of the Eastern and Southeastern States. Granite quarries predominate,
in New England and are plentiful in other Eastern States. Trap rock is important
in New Jersey, New York, and parts of New England.
 In the Middle Western States limestone quarries predominate, but those in
other kmds of rock are scattered widely, notably in the gramtes of th~ Northern
States. Throug~hout the* Rocky Mountain* area quarries are relatively few,
on the Pacific coast most are in rocks other than limestone.
 Quarries are most numerous in the thickly populated areas of the Eastern,
Middle Western, and Pacific Coast States because large demands for highways
and buildings have fostered the development of many producmg umts Our stone
resources are enormous and widely distributed Their development depends primarily
on local market demands Stone is available within reasonable reach of virtually
every important market area
 Commercial and noncommercial operations .—T he following table shows
the production of crushed stone for concrete and road metal and railroad
ballast during recent years by Government agencies of various kinds contrasted
s~ith that by commercial enterprises. Pro. duction by commercial companies
increased 37 percent in 1941 compared with 1940, whereas production by Government
agencies declined 7 percent Seventy-one percent of the total production was
made by commercial compames

Concrete and road metal and railroad ballast sold or used by commercial and
noncommercial operators in the United State8, 1987—41

[Figures for noncommercial operations represent tonnages reported by States
counties municipalities and other Government agencies, produced either by
themselves or by contractors expressly for their consumption, often with
publicly owned equipment; they do not include purchases from commercial producers.
Figureifor "commercial operations"represent tonnages reported by all other
producers]
Year
Commercial operations



Noncommercial operations



Total


Short tons
Aver-

age

value

per
ton
Percent
of change
in quan-
tity
from
preced-
ing year
Per.
cent of
total
quan-
tity
*
Short tons
Aver-
age
value
per
ton
Percent
of change
in quan-
tity
from
preced-
ing year
Per.
cent of
total
quan-
tity
Short tons
Percent
of change
in quan
tity
from
preced
ing year
1937   
1938 - - --
1939   
1940   
194L~ -
62,315,350
60,254, 170
59,516,270
63,203,240
86,360, 120
$0.88
.88
.86
.87
.91
+8.4
—3.3
—1.2
+6.2
+36.6
70. 5
63.6
57.3
63.0
71.4
26, 117, 220
34,508,880
44,374, 750
37,065, 150
34,603,790
$1.06
1.04
.97
1.02
1.04
—12.3
+32. 1
+28. 6
—16.5
—6.6
29.5
36.4
42.7
37.0
28.6
88, 432,570
94, 763,050
103,891,020
100,268,390
120,963,910
+1.3
+7.2
+9.6
~-3. 5
—~0. 6
 Method$ of transportation.—The following table shows the quantities
of concrete and road metal conveyed during 1940 and 1941 by each of the principal
methods of transportation.