124 CEMENT MATERIALS AND INDUSTRY. [bull. 
Boulder being near its western edge, while Fort Collins, Big Thorn 
son, Berthoud, Valmont, and Marshall lie on or near its east! 
border. This belt thins out southward near Golden, turns sligh 
east of south at a point just east of Morrison, and disappears west 
Larkspur. 
Another belt commences about 10 miles north of Colorado Spring 
and covers a wide area east and west of the Denver and Rio Gran 
Railway. The towns of Colorado Springs, El Paso, Fountain, Puebl 
and St. Charles are located on this limestone belt, while Sunview a 
Turkey Creek lie on its west border. Arms of this belt are extend 
up Arkansas River as far as Canyon, and up Huerfano River to Hu( 
fano Park, reaching almost to Dixon. The stations of Granero, Hu 
fano, Cucharas, Santa Clara, Placito, Walsenburg, Apishapa, 
Trinidad are located on the southern portion of this belt. 
> 
PORTLAND-CEMENT INDUSTRY IN COLORADO. 
Only one Portland-cement plant is at present in operation in O 
rado, but several attempts have been made to manufacture cem 
in the State. The materials used at the present plant, as well as 
all the previous plants, are limestones of various grades of puri ( 
from the Niobrara formation. 
The plant of the Portland Cement Company of Colorado is locat I 
about 8 miles east of Florence, Fremont County, south of Arkaij 
River. The materials used are an argillaceous limestone averagi 
about 71 per cent of lime carbonate, and a purer limestone carry 
about 88 per cent of lime carbonate. The former occurs in seve 
beds, aggregating about 60 feet in thickness; the purer limestone 
taken from a 40-foot bed lying about 50 feet below the other, 
rotary kilns are in place, using oil from the Florence field as fuel. 
BIBLIOGRAPHY OF CEMENT RESOURCES OF COLORADO. 
Lakes, Arthur. Building and monumental stones of Colorado. Mines and Mine: 
vol. 22, pp. 29-30. 1901. 
Lakes, Arthur. Sedimentary building stones of Colorado. Mines and Minerals, ^ 
22, pp. 62-64. 1901. 
Ries, HEiNRicn. The clays and clay-working industry of Colorado. Trans. 1\ 
Inst. Min. Eng., vol. 27, pp. 336-340. 1898. 
PORTLAND-CEMENT RESOURCES OF CONNECTICUT. 
While many outcrops of limestone occur within the limits of i 
State of Connecticut, few of them, unfortunately, are large enouj " 
to justify the erection of a cement plant. In addition to this disai 
vantage, most Connecticut limestones carry entirely too high 
percentage of magnesium carbonate to be considered available 
ii* 
