Qgg a VO«S CTAT1 Ml -I I'M 



,»;,„;,!• tbe [ron Clad brand shorn: 



21.5 



} 10.5 



ti ) 



63 - 5 



1-8 



-4 



1-8 



J ceniont manufactured at these works, and is dis- 



I -nelly later in this pa] 



Helderberg cement co. The plant of this company is located at 



\ e, Schoharie co. Quarries in the Waterlime group at 



1 1 lis point have been long- used for the manufacture of natural 



lent, while quarries higher up, both geologically and topo- 



phically, furnished a very pure limestone which was burned 



into lime. 



In 1898, the Helderberg cement co. began to utilize the stone 

 from these latter quarries in the manufacture of Portland cement, 

 ed on a small scale, the industry would seem to have 

 promised favorable results, as a much larger plant, belonging to 

 the same company, was erected during 1900. The new plant has 

 a nominal capacity of 1500 barrels a day. The materials used 

 are limestone and clay. 



As noted above, the limestone used for Portland cement is ob- 

 tained from the old lime quarries, and the clay from a deposit 

 in the vicinity. Smidth ball mills and Davidsen tube mills are 

 i for crushing, reducing and mixing the materials. The wet 

 process is employed and 12 rotary kilns are in use. The result- 

 _ clinker is ground in ball mills and tube mills, and the product 



keted as the " Helderberg " brand. 

 Th( as quarries at Howe Cave show exposures of the dif- 



fei rmations from the Clinton up to the Pentamerus. Dr 



I". II. Min. ind. C: 97. 



