156 EARTHS. SILICEOUS. 48. Lazulus. 



fonellana. Hard, rifty internally, of an iipperfeftly conchoidal frac- 

 ture inclining; to the even. 



Porcelliinice. Ki^nvan mineral, i. 'p. 313. 



Porcelane Jalper. SchmeiJJer mineraL i, p, 125. 



Porcelane Jalper. Ihomfun chem, 3. p. 533« 



Found in large compail layers, and frequently between the 

 fiffures of Bafaitcs, in Bohemia and Saxony : has an arid ap- 

 pearance when broken, like dried cluv, and is full of cracks 

 "* or flits; and is fuppofed to have been altered by the adior of 



fire: fpecific gravity 2,330, contains filica 60,75. a^'^mina 

 27,25. magnefia 3,00. oxyde of iron 2,50. potafs 3,60. 

 Ro/e. 



tvulgarist - Hardifh, fhining or polifhed internally, of one uniform 

 colour or veined or fpotted. 

 Jafpis. Cronfi, mineral, fe^. 63. 65. 

 Common Jafper. Kirivan mineral, i . p, 3>0- 

 Comraon Jafper. Schmeifser miner, i. p. 126, 

 Comrnor; Jafper. ThumJ'on chem. 3. p, 533. 



1, Of one uniform colour. 



Silex Jafpis. Syst. nat. xii. 3. p, 71. n. 13, 14, 

 Jafpis panic. fubtilifT, Wall.JyJi, i. p. 297. n.i. 



2, Variegated. 



Jafpis partic, fubtilifT. Wall, J'vji- i. p, 299. n. 2. 



Found in Germany, Saxotiy, Sileiia^ Hungary, &:c, in large 

 compadl maffes, fometimes coarfely interfperfed in alternate 

 layers with other flones, and often in obtufe angular pieces: 

 colours difi'erent fhades of black, white, yellow, red, brown, 

 and green, often variegated, fpotted or veined with feveral 

 colours : is frequently enriched with iron and gold ores, 

 and admits a fine polilh : frafture conchoidal, or fometimes 

 imperfeftly foliated; fpecific gravity from 2,530. 102,700. 



^8. LAZULUS. Confiding of filica, with a lefler 

 proportion of alumina and carbonate of lime, 

 and a fmall quantity of fulphate of lime aad 

 oxyde of iron: opake, hardifh, blue, denfe, 

 without internal luftre, breaking into indeternai- 

 nate fragments, producing a white powder when 

 pounded: neither lofmg its colour nor effervef- 

 cing from acids fprinkled on it, melting eafiiy in 

 the fire into a frothy flag. 



^ismaliSf Lazulus. 



Cuprum Lazuli. Syst^ nat, xii, 3, /.14s* ^* '^* 



