EARTHS. ARGILLACEOUS. 41. Scorlus. 
*39 
4t. SCORLUS. Confiding of alumina and filica, ' 
moftiy oxyde of iron, with frequently a little 
carbonate of magnefia and oxyde of manganefe: 
hard, breaking into indeterminate fragments, 
fhining internally, parafitical: not effervefcing 
with nitric acid, and eafily melting into a glafs. 
W^hite, hardifh, fufible in the fire with fonie difficulty, 
eafily mouldering. 
Graniti vianchi. Gi^vani lotolog. Vefwv. p. 38. 
Bergman de prod, niulcan. opuj'c. mol. 3. p. 206, 
, Shorl, Bafaltine, White Garnets. Kirnman 1. p, 285. 426. 
Volcanic Shorl. Schmeifter miner. l. p. 85. 
Leucite. Thomfon chem. 1./. 552. 
Found in the Lavas of Vefumim, where it appears, according to 
Kirmeart, to have pre exilled in the rocks which were the 
mother Hones or bafts of lavas before the eruption, and is not 
formed by fubfequent percolation through, and cryftallization 
in the melted lava : colour white or greyilh-white ; it is al- 
ivays found in cryilals, the primitive form of which are ei- 
ther cubes or rhomboidal dodecahedrons ; texture foliated : 
fradlure more orlefs conchoidal ; it is fometimes tranfparcnt, 
but opake whan decompofing : its powder caufes fyrup of 
violets to afl'ume a green colour : is hardly fufible before the 
blowpipe, and gives a white tranfparent glafs with borax ; 
fpecihe gravity from 2,455. 2,490. contains filica 54. 
alumina 23. potafs 22. iron o. Klaproth, 
Brittle, fhining, of a tninutely conchoidal texture, cafily 
melting before the blowpipe with froth into a hard 
black enamel. 
Thumerflone. Kirnuatt miner, p.iyi, 
Thumerftone, Purple brown Schorl. Scbmeijfer \.p< 86. 
Thummerftone. Thomfon chem. 3. p. 596. 
1. Of a common fonn, diaphanous or fubopake, fpontaiieoufly 
falling into cruftofe fragments. 
2. In very fhining pellucid or femipellucid cryilals which are 
fomewhat prifmatic, with rhomboidal faces, generally ftriated 
longitudinally. 
Found near 7 herm ‘and Sthneeburg in Saxorri, near Bourg de 
Oifans in Dauphine, in the Pyrenean mountains, and in 
Korvjay near Kongihurgt colour clove-brown, fometimes 
inclining to red, green, grey, violet or black : is generally 
found in cryftals, the molt ufual of which are flat rhomboidal 
parallelopipeds with the oppofite edges a little truncated; the 
S 2 
