38 



calling there in company with my friend D. Turner, Esq., 

 and was lucky enough to procure some rich little pieces, 

 which served my purpose, and gave me the most satisfactory 

 pleasure of gratifying a few friends. According to the Rev. 

 Malachi Hitchings's account, in Phil. Transac. for 1801, 

 page 169, " the lode in which it occurs is one of those 

 cross courses which intersect and derange the copper lodes, 

 and are consequently of a more recent formation. No ores 

 of silver were observable in this lode till at the depth of 110 

 fathoms from the surface, and at the further depth of 32 

 fathoms they disappeared. The richest mass of silver ore was 

 found at the depth of 2 fathoms above the level at which 

 it disappears. About 108 tons of it are said to have been 

 raised. The silver ore, strictly speaking, is a mixture of 

 galasna, native bismuth, gray cobalt ore, vitreous silver ore, 

 and native silver." 



Our specimen seems to be the galaena decomposing and 

 •protruding the silver; itself remaining of a cinereous ap- 

 pearance, losing its natural brilliancy. There are also some 

 pyrites and bits of quartz. The silver protruded is nearly 

 pure, and has been (from its curling appearance) compared 

 by the people of Penzance to the scrapings of silver spoons. 

 The silver for coin and manufacturing is alloyed with copper, 

 which does not affect the whiteness, and is not easily de- 

 tected, unless in too great proportion, when it may some- 

 times be tasted. It may be made very thin as leaf silver, 

 one grain thus formed measuring more than 51 square 

 inches. It is often used to plate over copper or iron, and 



