ORDER VII. RHOMliOHEDUAL QUARTZ. 331 



lian is brought from Arabia, India, Surinam, and Siberia ; 

 it is met with also in Bohemia, Saxony, &c. ; fibrous Car- 

 nelian in Hungary ; Chrysoprase at Kosemutz in Silesia, 

 and at New Fane in Vermont, North America, in both 

 places in serpentine. It is not known from whence the 

 ancients received the Plasma found among the ruins of 

 Home, but several varieties resembling it have been re- 

 cently discovered in Moravia and Bavaria. It occurs in 

 India, from whence it is occasionally brought in the shape 

 of beads and other ornaments. Flint is a common mineral 

 in England, France, the islands of Rligen and Seeland, in 

 Poland, Spain, &c. Near Gratz in Stiria it occurs as one 

 of the ingredients of gneiss. Splintery Hornstone produces 

 the remarkable pseudomorphic crystals from Schneeberg in 

 Saxony ; it also occurs in veins in Hungary and other mining 

 countries ; in beds it is found in Norway, and in spheroidal 

 masses in limestone in the Tyrol. The locality of conchoi- 

 dal Hornstone is the isle of Cyprus. Flinty slate forms beds, 

 and occurs also in pebbles in Bohemia, Silesia, Saxony, Hun- 

 gary, in the Hartz, in France, &c. ; fibrous Quartz in the 

 Hartz ; Cat's eye in Ceylon, the coast of Malabar, and it is 

 said also in the Hartz. Heliotrope used formerly to be 

 brought from Ethiopia, but is now generally obtained from, 

 Bucharia, from Tartary, and Siberia. Iron flint is frequent 

 in the ironstone veins of Saxony, Bohemia, Hungary, Tran- 

 sylvania, &c., and along with it often also common Jasper. 

 Striped Jasper occurs in Siberia, at Gnandtstein in Saxony, 

 at Ivybridge in Devonshire ; the brown Egyptian Jasper 

 conies from the banks of the Nile ; the red variety from 

 Baden. The petrifactions, still preserving the rings of 

 wood in the shape of trunks, branches and roots, are met 

 with in many countries. 



6. Several varieties of rhombohedral Quartz are of im- 

 portant use in the arts and manufactures. Some of those 

 of good transparency, or fine colours and delineations, as 

 Rock-crystal, Amethyst, Rose-quartz, Chrysoprase, seve- 

 mi varieties of Calcedony, called Onyx, Sard, Sardonyx, &c. 



