SCHORL. 





Protoxide of irou 



. 6-19 



Magnesia . 



. 2 58 



Lime .... 



. 0-50 



Soda .... 



. 1-89 



Potash 



. 0-65 



Phosphoric acid . 



. 0-12 



Fluorine 



. 1-49 



100-00 

 According to Gmelin, the Bovey Tour- 

 maline consists of 2Na, Ca, I\Ig, 14Fe+ 2-Fe, 



22^1 + 24Si+4B. 



BB intumesces and forms a black scoria- 

 ceous mass. With borax fuses to a trans- 

 parent glass, and gives the reaction of iron. 

 With soda yields a manganese reaction. 

 With Fluor colours the flame green. 



Decomposed by concentrated sulphuric 

 acid, after fusion. 



Localities. — English. Cornwall : Bos- 

 cawen Cliffs and Botallack mine, near St, 

 Just ifigs. 374 and 376), St. Michael's Mount, 

 &c, ; Devonshire, at Chudleigh, near Bovey 

 Tracey (^fig. 375), in granite, associated 

 with fine translucent crystals of white Apa- 

 tite. — Scotch. Portsoy, in Banffshire, in 

 large curved crystallized prisms, imbedded 

 in granite. — Irish. Stillorgen, co. Dublin. 

 — Foreign. Karosulik, in Greenland. The 

 Ural. Arendal, in Norway. Horlberg, near 

 Bodenmais, in Bavaria. Kariubricka, in 

 Sweden. The Harz. The Tyrol. The Py- 

 renees. Saxony. Haddam, Connecticut, 

 U. S. Madagascar. 



Name. After Schorlau, a village in 

 Saxony, near which it was first found. 



According to v. Kobell, the name is de- 

 rived from the old word Schot-, meaning 

 uncleanness (impurity) ; because Schorl ap- 

 pearing in a deposit of Stream Tin renders 

 the Tin Stone impure. Kirwan, on the 

 other hand, states the word Schorl to be 

 derived from the Swedish Shorl (brittle), 

 and to have been " first used by Cronstedt, 

 to denote a class of stones of a columnar 

 form, and considerable hardness and density, 

 their specific gravity being from 3 to o-4." 



" It seems that the word Shorl has often 

 been applied to stones of various species, not 

 only by different writers, but often by the 

 same author. Cronstedt, Wallerius, Berg- 

 man, Saussure, Rome de Lisle, and the older 

 mineralogists, included several distinct 

 minerals under the common name of Shorl. 

 Cronstedt translated the word into Latin 

 hy basaltes, ^v\nch increased the confusion; 

 an instance of which is afforded by the mis- 

 take made by Wallerius, who, deceived by 



SCHORLOMITE. 337 



the name (basaltes crystallisatus, by which 

 Cronstedt translated Shorl crystal), com- 

 prehended also the columns of the Giant's 

 Causeway under that species. Rome de 

 Lisle constantly confounds Schorls, Actino- 

 lites. Tourmalines, and Basaltic Horn- 

 blendes." — Kirwati's 3Iin. vol, i. 



Schorl was confined bj^ Rammelsberg to 

 varieties of L-on Tourmaline. Hermann, how- 

 ever, divides Tourmaline into three groups, 

 and only includes under the name Schorl 

 those varieties which polarise light. 



Brit. Mus., Case 40. 



31. P. G. Horse- shoe Case, Nos. 844, 

 866—871. 



Schorl Aigue - aiARmE. The name 

 given by Saussure to cr3'stallized olive- 

 green Epidote {Delphinite), from Dauphiny, 

 on account of the very brilliant lustre re- 

 flected from its surface, and the high polish 

 of which it is susceptible. 



ScHOKL Blanc, Rome de Lisle. See 

 Albite. 



Schorl Crystallise Opaque Rouge, 

 von Born. See RuTiLE. 



Schorl Electrique, Haily. See Tour- 

 maline. 



Schorl Xoire, Brochnnt. See Schorl. 



Schorl Rouge, Saussure. See Rutile. 



Schorl Transparent Lenticulaire, 

 Rome de Lisle. See Axinite. 



Schorl Transparent Rhomboidal, 

 Rome de Lisle. See Tourmaline. 



Schorl Violet, Dufrenoy. See Axi- 

 nite, 



ScHORLARTiGER Beril, Werner. See 

 Topaz. 



ScHORLiTE. A name that was given to 

 Pycnite, in the belief that it was a white 

 variety of Schorl. 



Schorlomite, Shepard. Massive, with 

 indistinct cleavage ; also in hexagonal 

 prisms, the lateral edges of which are trun- 

 cated by narrow and brilliant planes. 

 Colour black, often with a blue tarnish and 

 pavonine tints, causing a resemblance to 

 Specular Iron, for which it has been some- 

 times mistaken. Lustre vitreous. Streak 

 greyish-black, inclining to lavender. Frac- 

 ture conchoidal. H. 7 to 7*5. S.G. 3-8. 



Comp. Ca5 fei + Fe Si + Ca li3 =: silica 

 24 9, oxide of iron 21*9, lime 30"7, titanic 

 acid 22-5 = 100. 



Analysis, by Rammelsberg ; 



Silica 25-24 



Peroxide of iron . . . 20-11 



Titanic acid .... 22-o4 



Lime . . . . . 29-38 



z 



