AND ASSOCIATED PERMIAN ROCKS OF DURHAM. 225 



No. 45. Locality— FUL WELL QUARRY. 



"MAIN OR HONEYCOMB STONE." 



Lithological Characters. — Light grey, hard, suh-crystalline, 

 highly concretionary, the concretions being formed (in specimen 

 analysed) of concentric laminae with unequal open spaces be- 

 tween, which are coated with yellow magnesian marl ; unfossili- 

 ferous. Occurs in massive beds that form a series twenty feet 

 thick and upwards. 



ANALYSIS. 



Carbonate of lime 96'55 



magnesia T46 



Sand, clay, oxide of iron, &c 1-06 



Water, &c 093 



100-00 



This limestone is considered to make the best lime for tillage 

 in the North of England. For this purpose it is largely burnt 

 at the Fulwell Quarries and shipped to Scotland. 



It forms a building stone that resists atmospheric action ; but 

 it is difficult and expensive to dress. It has been very largely 

 used from the Half-way House Quarries in the execution of vari- 

 ous works, both in and out of water, at the South Docks, Sun- 

 derland. A stone of exactly similar character has been used for 

 the Cleadon works of the Sunderland and South Shields "Water 

 Company. It was also in former times, when the site of the 

 present Mowbray Park existed as Building Hill Quarry, exten- 

 sively used in Sunderland for building purposes, though chiefly 

 for rough walling. 



Nos. 46 and 47. Locality— FULWELL QUARRY. 



Lithological Characters. — Grey concretions, imbedded in soft 

 yellow magnesian marl ; unfossiliferous. This specimen forms 

 two analyses : the grey concretions one, the marl the other. 



