Geology of Coalhrook Dale, 



487 



No. Local Names. Description of the Beds. 

 99. Little flint coal Slate-coal 



100. Rock in the coal Fine hard white sandstone, slightly micaceous 1 



101. Lower little flint-coal Slate-coal 



102. Little flint Hard, fine, white sandstone 1 



103. Crawstone measure Hard, fine sandstone, light brown, slightly mica- 



ceous and bituminous 1 



104. Coal under ditto Slate-coal 



105. Crawstone crust Whitish, fine, rather friable sandstone 1 



106. Lancashire ladies' coal Fibrous coal 



107. Rock, very hard White, compact sandstone, containing numerous 



quartzy pebbles 



108. Ditto Compact, white, argillaceous sandstone, slightly 



oolitic 1 



Deep Pit. 



yds. ft. in. 



4 



2 3 



231 1 230 1 11 



Basset Pit. 

 yds. ft. in. 



4 



1 2 

 2 3 



2 1 



The last stratum immediately overlies the Wenlock Limestone at Lincoln Hi! 



6 

 10 

 2 3 

 9 



1 



1 1 6 



MINERALS OF THE COAL MEASURES. (B.) 



AiiRAGONiTE Occurs with barytes, but rarely. 



Barytes, crystallised Beautiful crystals occur in the large nodulesof ironstone from the bituminous 



shale overlying the little flint coal in Broseley and Caughley parishes. 



Charcoal, mineral Common in the fungous and some of the upper coals, forming thin laminae 



alternating with others of the crystalline coal : — also in the sulphur coal 

 of Kingslow, where it is frequently iridescent from its admixture with 

 iron pyrites. — A few fragments of very pure mineral charcoal have been 

 found in some of the Penneystone nodules. 



Iron, carbonate, crystallised In the nodules of ironstone — principally the white flatstone and Penneystone. 



argillaceous Forms the nodules of the ironstone measure. 



earthy red ochre Occasionally forms nodules in some of the sandstones. 



peroxide Dispersed in small quantities throughout most of the strata, — Compacthema- 



litic masses occur in the large ironstone nodules of the little flint coal shale, 

 phosphate ....Rare. — In the Penneystone nodules. 



'"^^^rhes' *"""™"" ''■°" } Very abundant in some of the coal beds— called sulphur coals. 



arsenical Cryslets in ironstone nodules, and coal beds, — rather rare. Sometimes the 



arsenic volatilizes, and can be collected from the blast furnaces, 

 hexahedral In ironstone nodules. — In detached masses in the interior of the Penney- 

 stone nodules. 



octohedral Ditto. ditto. 



rhombohedral ... Ditto. ditto. 



radiated Ditto. ditto. 



Lead, sulphuret. Galena Rare. — In the Penneystone nodules. 



Lime, carbonate, crystalline In veins in the coal and in ironstone nodules. 



crystallised Beautiful tetrahedral crystals occur with the fragments of brown wood in the 



Penneystone nodules at Madeley, also rhomboidal and tetrahedral cry- 

 stals in the curlstone at Woombridge. 



Petroleum, viscid Occasionally in cavities in Penneystone nodules ; the white flats, crawstone, 



&c. — It is also commonly diffused throughout the central coal series, and 

 in the flint coal and roof at Caughley. 



Pholerite, of Guillemin Of frequent occurrence in crevices of the ironstone nodules, especially the 



Penneystone, in the casts of plants in ironstone, &c. 



Titanium Is not of rare occurrence in the hearthstone of the iron blast furnaces, where 



it is found both massive and in brilliant cubic crystals ; it exists naturally 

 apparently as titanic acid combined with iron and zinc. 



Zinc, sulphuret. Blende Common in almost all the ironstones, — frequently forms the casts of plants. 



— Beautiful dodecahedral crystals occur in detached masses in the 

 interior of the Penneystone nodules, and in the casts of shells, 

 cadiniferous Occurs in the Penneystone nodules and the white flats, but rarely. 



