CLAYS OF OCEAN COUNTY. 489 



The material has more value as an ochre or mineral paint, and 

 is said to have been used to some extent in the manufacture of 

 oilcloth. Its high percentage of iron oxide and low silica con- 

 tents can be seen from the following analysis : 



Analysis of an ochreous yellow clay. Tilton's pit, Toms River. 



Silica (S1O2), 3I-96 



Alumina (A1 2 3 ), 21.93 



Ferric oxide (Fe 2 3 ), 31-39 



Lime (CaO), 0.45 



Magnesia (MgO), 0.18 



Loss on ignition (chiefly H 2 0), 12.92 



Total, 98.83 



Total fluxes, '. 32.02 



The high percentage of water, as compared with the low 

 amount of alumina, is due to the iron oxide being present as 

 limonite, which has about 14 per cent, of chemically combined 

 w r ater. The clay contains approximately 36.00 per cent, of limon- 

 ite. 56 per cent, of clay base and 8 per cent, of sand. 



Herbertsville. — A thinly laminated clay often very sandy and 

 elsewhere very plastic, occurs at a number of points south of Her- 

 bertsville (Loc. 218, 219). It differs somewhat in appearance 

 from the Cohansey clays found elsewhere in the county, but it 

 seems on the whole probably referable to> that horizon. Whether 

 the various outcrops are parts of a continuous bed or a series of 

 closely lying lenses it is not possible to say. The clay has been 

 opened up by the Herbertsville Brick Company at their yard, and 

 -at Isaac Tilton's yard, south and southeast of Herbertsville, re- 

 spectively. 



At the former (Loc. 218) the clay is exposed in a shallow ex- 

 cavation 200 feet long, 20 feet wide and about 4 feet deep. It 

 varies from a very plastic clay to one of very sandy character 

 with interlaminated beds of sand. By digging a large quantity 

 at once and piling it up the two kinds become more or less mixed. 

 The clay, sandy as it is, is riot used alone, however, but a large 

 quantity of sand obtained from a separate pit near by is added to 

 it. The effect of this addition is very marked, as can be seen 

 T>elow, where the tests are given in parallel columns : 



