298 ORIGIN AND DEVELOPMENT OF ORE-DEPOSITS. 



depth of over 60 fathoms from the surface. Proceeding north- 

 ward and westward, veins of this series have been worked to a 

 greater or less extent at Knightor and Treverbyn, Eosevear, 

 Treskilling, Lanjew, Coldbriggen, Withiel, and Pawton, the 

 depths attained hitherto in these mines varying from 20 to 40 

 fathoms from the surface. The Pawton lode* bears 18° W. of N., 

 and underlies eastward about 1 foot in a fathom ; it varies from 

 about 1 to over 30 feet in width, averaging from 6 to 8 feet, 

 where worked. The lode is in one place heaved by an E.W. 

 vein which perhaps belongs to class XIV, it underlies about 

 1^-feet in a fathom northward. This vein is generally very 

 quartzose, and the iron lode is much more siliceous than 

 usual near the junction, while the intersecting vein itself 

 contains some iron ore near that point. It has not been 

 explored to any distance away from the iron lode. Parallel 

 lodes containing iron ore are known to exist on either side of the 

 main lode, but these have only been worked on to a very small 

 extent. These red hematite veins, which are usually very free 

 from quartz, are crossed by a series of veins of brown hematite 

 containing much quartz at Coldreath, Savath, Canna, and other 

 places, as already stated. 



More to the north are a number of lead lodes, coursing 

 about 20° W. of N., some of which contain copper ores also. 

 That which passes down Halwin Creek and crosses the Camel 

 near Cant Hill, is probably the direct continuation of the Pawton 

 lode ; another which passes from Little Petheriek to the head of 

 Credis Cove, has been worked somewhat considerably at Credis 

 mine ; and a third having a similar direction has been slightly 

 worked a furlong or so westward of St. Merryn churchtown. 

 Between the Halwin and Credis veins is the great N.S. fault 

 which cuts through Padstow, extending from Dinas Cove to the 

 Day-Mark, a distance of nearly 4 miles. I am informed that 

 this also has yielded lead ores in the neighbourhood of Padstow. 



Keeping along by the N. coast and passing westward for 

 several miles farther, we arrive at the group of lead veins, 

 bearing almost exactly N.S., which have been worked in the 

 neighbourhood of Trewollock, Trewinnick, Trewinnel, and 

 Trethollan, in the neighbourhood of St. Columb and Newquay. 



* Rollins, Rep. Miners' Assoc. Corn, and Devon, 1875, p. 27, 



