SAND AND GRAVEL. 239 



Chesterfield, and 5 in Nansemond. The total production of these 4 counties 

 amounted to $1,219,090 or 82.72 per cent, of the total production for the 

 entire Coastal Plain region. 



SAND AND GRAVEL. 



Sand and gravel are found in almost every one of the Coastal Plain 

 formations. The sands of the Virginia Coastal Plain region are employed 

 as building sand, molding sand, engine sand, and in the manufacture of 

 sand-lime brick. Gravel and sand are also used for road-building. 



Sand. — Sand, both coarse and fine, is found in almost every one of the 

 Coastal Plain formations. At times the sand consists of pure quartz grains, 

 but at other times is mixed with more or less clay or gravel and occasionally, 

 particularly in the Potomac deposits, arkose forms the matrix for the sand 

 grains. These are sometimes covered with a ferruginous coating which 

 tends to bind the grains together. Ferruginous sands pack together much 

 better than the pure quartz sands and hence afford much finer roads where 

 they form the surface materials. The very sandy roads common in the 

 eastern part of the State are caused by the absence of binding material to 

 hold the solid grains together. 



The better grades of sand have been locally used in great quantities for 

 building purposes. Some of the sands are probably pure enough to be 

 utilized as glass sands although none have been employed for that purpose 

 hitherto. In New Jersey some of the Miocene quartz sands have been used 

 in the manufacture of glass, and doubtless the same formations in Virginia 

 contain equally desirable materials for glass-making. 



Molding sand has been obtained from several pits along Gillis Creek in 

 the southeastern part of Eichmond, and is of very good quality. Most of it 

 is used in Eichmond although some has been shipped elsewhere. This sand 

 belongs to the Aquia formation and contains considerable glauconite, a 

 constituent of all the Eocene sands. The deposit is of a pepper and salt color 

 with certain portions stained brown by the iron oxide produced in the 

 decomposition of the glauconite. There are at times small pebbles in the 

 sand while certain beds contain casts of fossils. Sand with apparently 

 similar characteristics is found throughout the Aquia formation, so that it 

 is probable that much material suitable for molding purposes can be obtained 

 from this formation throughout the Virginia Coastal Plain region. In 

 Maryland some of the slightly arkosic sands from the Potomac deposits have 

 also been used as molding sands which suggests the probable occurrence of 

 equally desirable sands in the same formation in Virginia. 



