O F S T O N E S. &5 



We find it alfo, in the fame mines, in the form of incrufta- 

 tions, with various angular protuberances and efflorcfceiices, of 

 a dazzling fplendor. 



Pfcudo-Cnftal does not effervefce with Aquafortis, It is folvent 

 by fire, and is ufed in fluxing metals. 



Cryftal, of an hexangular fhape, is fometimes found under the 

 gravelly furface, and in the fiflures of the rocks, at Dunftonbroitgh- 

 caftle. It is mentioned by the learned editor of Camden, who 

 compares it ro the ^r//?&/-flones (b). I am informed that the late 

 Thomas Proffor, of Rock, Efq; fent fome for trial on the wheel to 

 Edinburgh, which proved not inferior to thofc flones for hardncfs 

 and luftre. Hence they obtained the name of Dunftonbrough dia- 

 monds, but they are fo rarely found, that the late Dr. Tovey, vicar 

 of Embleton, on letting his tithes jokingly faid, " That he referved 

 only to himfelf tile tythe of the diamonds." 



No folvent has been hitherto found for Cryftal. 



Small opake and pellucid cryftalline nodules are not unfre- 

 quent on our frefli water and fea ftrands, from which I have had 

 the following varieties. 



\ft. Of an oblong figure, and fiattifh on one fide, with an ad- 

 mixture of a pale yellow, and a deep red, in fpots and clouds. 

 From the fea-ftrand near Alnmouth. 



idly. Of a round ifh figure, grey, with an admixture of a deep 

 red, diffufed in clouds, emulating the mofs-like figures in the 

 Af0r<2-ftone. From the fliorc of the brook below the bridge at. 

 Simonburn. 



(b) Bifliop Gibfon. 



