:el.] 
CONNECTICUT. 
125 
rtland-cement materials. This last statement is particularly true 
the thick and extensive limestone beds of western Connecticut, 
ich are so extensively quarried and utilized for lime burning in the 
inity of Danbury, Canaan, etc. Numerous analyses of these lime- 
nes show that they rarely carry less than 20 per cent of magnesium 
bonate, while they often run as high as 4:0 per cent of that constit- 
lt. The nonmagnesian limestones, on the other hand, which occur 
eny in central and eastern Connecticut, are rarely over a few feet 
hickness, or else have a very limited area of outcrop. 
)f the analyses given below Nos. 2 and 3 are fairly typical of most 
the limestones of western Connecticut. They are in general quite 
*e, carrying usually very low percentages of silica, alumina, iron 
de, etc., but they are at the same time almost invariably high in 
Frnesia, often approaching dolomite in composition. Occasionally 
s are found which show very low magnesia percentages. An 
mple of this is afforded by analysis No. 1. Such limestones would 
course be serviceable as Portland-cement materials, but the trouble 
hat these low-magnesia beds are not extensive, nor can they be told, 
sight, from high -magnesia rocks occurring in the same quarry. It 
rid therefore be impracticable to separate the two kinds of rock 
ing quarrying, and for this reason the writer believes that such 
asional occurrences of low-magnesia rocks give no promise of a 
ure Portland-cement industry in Connecticut. 
Analyses of limestones from Connecticut. 
•a (Si0 2 ) 
mina (A1 2 3 ) . . 
i oxide (Fe 2 3 ; 
e (CaO) 
;nesia (MgO) .. 
5.83 
3.90 
50. 40 
.10 
Don dioxide ( C0 2 ) 30. 72 
0.08 
.25 
30. 40 
21.48 
47.58 
0.48 
.20 
31.31 
21.03 
46.98 
Quarry of Danbury Lime Company, Danbury, Fairfield County. Mineral Resources U. S. for 1889- 
p. 386. 
Quarrv of Canaan Lime Company, Canaan, Litchfield County. Twentieth Ann. Rept. U. S. Geol. 
ey, pt. 6, p. 370. 
Quarry of Canfield Bros., East Canaan, Litchfield County. Ibid. 
PORTLAND-CEMENT RESOURCES OF DELAWARE. 
o limestones occur within the limits of Delaware, with the excep- 
of small isolated outcrops in the crystalline rocks of the extreme 
thorn portion of the State. Though some of these furnish rock 
in magnesia, the outcrops are entirely too small to be worth 
sidering. 
