46 



MINERAL RESOURCES OF ALABAMA. 



Table III. Composition of Lower Carboniferous (Bangor) Lime- 

 stone. 



Physical Character. The Bangor limestone is a limestone of 

 normal hardness, and cannot therefore be quarried so readily 

 and so cheaply as the Cretaceous andi Eocene limestones to be 

 discussed later. Limestones resembling 1 the Banger in hard- 

 ness are successfully utilized in Portland cement manufacture 

 in New York, Ohio, Indiana, Missouri, and other states; so 

 that this character aloiie need not be considered as rendering it 

 unavailable. Its hardness is, moreover, largely counterbalanced 

 by the fact that as quarried it will be practically free from water, 

 and will, therefore, require the expenditure of little coal for 

 complete drying. 



Accessibility to Clay or Shale. Thick deposits of shale of 

 (?oal Measures occur near the outcrops of the Bangor lime- 

 stone in the vicinity of Birmingham. In some parts of the val- 

 ley to the northeast of Birmingham excellent beds of clay at 

 the base of the Lower Carboniferous formation, are quite ex- 

 tensively developed. Both the overlvingr shales and the under- 

 lying clavs have been worked to some extent in this region, the 

 product being used in brick and notterv manufacture. "Exami- 

 nation of 'a series of analyses of these shales and clavs as well 

 as of some clavs belonging to the Cretaceous formation and oc- 

 curring in close proximity to some of the limestone quarries in 

 the Tennessee Valley, shows that all of these deposits could fur- 



