OTHER REf^OURCES OF MICHIGAN 111 



Chester, Lima, Qiiiney, Grass Lake, and Brighton. 

 This distributed the industry widely over the entire 

 Lower Peninsula of Michigan, thus utilizing the 

 widely extended marl and limestone deposits and 

 distributing the output widely among the consumers. 

 That output in 1918, according to the United States 

 Geological Survey, was 3,554,872 barrels, a decrease 

 from the 1917 production of 4,088,899 barrels.^ It 

 is economically desirable that cement factories should 

 be erected in the Upper Peninsula to supply the 

 local requirements. There is al)undant raw material 

 available, and wliile the local market is not as ex- 

 tensive as in the southern portion of the State, it 

 exists and might well be supplied from a plant within 

 the district. 



Limestone is distributed widely over the State, but 

 that of commercial importance is found chiefly in 

 the northern portion of the Lower Peninsula and 

 in the eastern part of the Upper Peninsula. De- 

 posits here lie close to transportation routes by rail 

 or water, and in recent years have been largely ex- 

 ploited. These limestone formations contain de- 

 posits of a high calcium carbonate content, which 

 have been utilized as fluxes in blast furnaces at 

 Sault Ste. Marie, Marquette and Duluth, at the 

 carl)ide works at Sault Ste. Marie, and at the copper 

 smelters in the copper country. The purity some- 

 times attains 98 per <^'ent of calcium carbonate. The 

 dolomites which are also found here and elsewhere 

 in the State, while utilizal)le as linings for open 



'"Ccmont in IHIS'': V. S. Geol. Survey, p. 572. 



