391The Mineral Industry of Maryland 
 
This chapter has been prepared under a cooperative agreement between the
Bureau 
*of Mines, U.S. Department of the Interior~ and the Maryland Geological Survey
for collecting information on all minerals except fuels. 
 
 
1~y Curtis D. Edgerton1 
 
 
Value of mineral production in Maryland declined 2 percent from that of 1966.
Stone remained the leading commodity in value, accounting for 39 percent
of the total value of all minerals produced, with sand and gravel accounting
for 24 percent. Almost 20 percent of the value of all mineral production
resulted from operations in Baltimore County. Carroll, Frederick, and Washington
Counties also contributed heavily to the value of minerals produced. The
only counties reporting no mineral production were Queen Annes and Somerset.

The Maryland Geological Survey published a new State Geologic Map with 
cross sections. This replaced the map issued in 1933. The Maryland Survey,
in cooperation with the U.S. Geological Survey, also undertook a geologic
mapping program in Baltimore, Cecil, and Frederick Counties. 
The U.S. Geological Survey issued reprints of 16 topographic quadrangles
within or including parts of Maryland. In addition, the Survey revised the
Riley Quadrangle, published a Hydrologic Investigations Atlas on the water
resources of the Patuxent River Basin, an aeromagnetic map of Baltimore County
and Baltimore City, and a corresponding bouger gravity map. 
 
1 Geologist, Bureau of Mines, Pittsburgh, Pa. 
 
Table 1.—Mineral production in Maryland' 
 
1966 
 
1967 
 
Mineral 
Quantity 
Value 
 
(thou- 
 
sands) 
Quantity 
Value (thousands) 
Clays thousand short tOns...Coal (bituminous) do_...Gem stones          
                             
2856 
1,222 NA 
2 $1,084 
 4,367 
3 
998 
1,305 
NA 
$1,462 
4,548 
3 
LIme. short tons_Natural gas million cubic feet -Sand and gravel thousand
short tons -Stone do......Value of items that cannot be disclosed: 
29,447 
 696 
15,108 
13,868 
 386 
 181 
20,383 
27,229 
W 
621 
12,868 
14,479 
 W 
 159 
17,724 
28,581 
Ball clay 1966, cement (portland and masonry), greensand marl, peat, potassium
salts, talc and soapstone      
XX 
20,528 
XX 
20,342 
Total                                       
Total 1957—59 constant doilars_ 
XX 
XX 
74,161 
72,307 
XX 
XX 
72,819 
71,232 
 i' Preliminary. NA Not available. W Withheld to avoid disclosing individual
company confidential data. 
 XX Not applicable. 
 1Production as measured by mineshipments, sales, or marketable production
(including consumption by producers). 
 2Excludes bail clay; included with "Value of items that cannot be disclosed."