84 Mr. N. J. Winch on the Geology of 



In aggregated acicular crystals; opake; lustre silvery. From 



Allenheads and Aldstone moor. 

 Larger crystals of the same form : lustre adamantine. From 



the Teesdale mines. 

 Black acicular crystals ; Fair hill, Flow-edge. 

 Capillary crystals ; lustre silvery. On iron-stone. From 

 Allenheads and Teesdale. 

 Phosphate of Lead. — Botryoidal, of a pale dirty green colour. Grass 

 hill, Teesdale. 

 Of a siskin green colour, crystallized in small 6-sided 

 prisms, terminated by 6 planed acuminations, forming 

 clusters in light yellowish brown marly earth : from 

 Surside mines, Netherdale, Yorkshire. This ore yields 60 

 per cent, of lead, and makes a beautiful green pigment. 



The following ores of lead also occur -, green, yellow, and white 

 lead ore investing galena, from Allenheads and Aldstone moor: 

 coherent earthy lead ore of a dirty white colour, without lustre, 

 worked in considerable quantity at Grassfield mine near Nent head : 

 lead ore of a whitish grey colour, resembling scales of mica, the 

 white sill of the miners, from Allenheads, &c. : friable earthy lead 

 ore of a dark reddish-brown colour, from Aldstone moor, &c. 



Ores of Copper, 



Copper pyrites with galena from Cross gill, Aldstone moor. 



Azure Copper ore, — In very small nodules imbedded in opake white 

 heavy spar ; found in small quantities at Wessinghope lead 

 mine near Stanhope in Weardale in the great limestone. 



Malachite, — Small quantities occur in the Dufton lead mine. 



