190 INDTCOLITE. 



of fracture. Colour white or grejnsli, some- 

 times with a tinge of brown, from an ad- 

 mixture of Garnet. Scratches glass. S.G. 

 2-74. 



Analysis, from India, by G. J. Brush : 



Silica 42-09 



Alumina .... 38"89 



Lime 15-78 



Soda ..... 4-08 



100-84 



BB infusible. 



Keadily gelatinises in acids. 



This mineral forms the gangue of Corun- 

 dum in the Carnatic (whence the name 

 Indianife), and is accompanied by Garnet, 

 Kvanite, Hornblende, &c. 



Brit. Mus., Case 19. 



Indicoltte, the name which has been 

 given to blue Tourmalines from their indigo- 

 blue colour. 



Brit. Mus., Case 40. 



Indigo Copper. See Covelline. 



Indurated Talc. A hard, impure variety 

 of slaty Talc. It occurs in nodules, with a 

 compact texture, at Little Cambray in 

 Arran; Portsoy in Banffshire; and 'Swi- 

 naness in Unst,'one of the Shetlands. 



Inflammable Cinnabar A name some- 

 times applied to Idrialite, in consequence of 

 its combustibility. 



Inolite. AformofCalcite. SeeOsTREO- 

 colla. 



Intire Metals. The name applied by 

 Kirwan both to "noble and perfect metals," 

 as well as to the "base and imperfect 

 metals,"^ and including those which are in 

 any degree malleable when cold. 



Iodic Mercury, Phillips. See Coc- 



CINITE. 



lODlTE, Brooke 8f Miller, Haidinger. loD- 

 siLBER, Leonhard. Iodic Silvei;, Phillips. 



lODINSILBKR, Mohs. lODURE d'ArGENT, 



Bevdant. See Iodyrite. 



lOD-QuECKSlLBER, Del Rio, Leonhard. 

 loDURE DE Mercure, Necker. See Coe- 

 cinite. 



loDOLiTE, Shepard. A meteoric mineral 

 found in small t}uantity diffused through 

 Chladnite in the stone from Bishopville. 

 Massive, in angular (somxewhat rounded) 

 grains, the largest of which are ^ inch in 

 diameter. Colour pale smalt-blue. Semi- 

 transparent. Lustre vitreous. Brittle. H. 

 5-5 to 6. 



55 fuses easily with ebullition to ablebby, 

 coloured glass, which while warm retains a 

 pale amethystine tinge. 



Name. From /w^'??, violet coloured. 



lOLITE, 

 Iodyrite. Hexagonal, with a highly j 

 perfect basal cleavage. Also occurs massive , 

 in thin plates of a greyish -white or silver- j 

 Avhite colour, which changes to lavender- j 

 blue on exposure to the atmosphere; also \ 

 citron- and sulphur- yellow, to yellowish- j 

 green. . Lustre resinous to adamantine, i 

 Transparent or translucent. Streak yellow. 

 Flexible in thin laminae. Sectile. H. about 

 1. S.G. 5-504. 



Fig. 242. 



i 



Fig. 243. 



Cowp. Iodide of silver, or Ag, I = silver 

 46, iodine 54=100. 



Analysis, by J. Lawrence Smith : 



Iodine 

 Silver 



. 63-109 

 . 46-380 



99-489 



BB on charcoal, melts instantly, giving 

 off a vapour which tmges the tlame of a 

 beautiful violet colour, and yielding globules 

 of silver. 



Localities. Guadalajara in Spain; form- 

 ing thin veins in Steatite at Albarradon, 

 near Mazapil, in Zacatecas ; and at Delirio 

 mines of Chanarcillo, near Copiapo in Chili, 



Iodyrite is homeeomorphous with Gree- 

 nockite. 



loLiTE, Phillips. Rhombic ; primary 

 form a right rhombic prism. Occurs crys- 

 tallized in stout prisms, which are often 

 hexagonal. Colour various shades of pale 

 and dark blue, sometimes with a tinge of 

 grey or brown. Exhibits dichroism ; often 

 appearing of a deep blue colour along the 

 vertical axis, but red, brownish-yellow, or 

 yellowish- grey when viewed by transmitted 

 light at right angles to the axis of the 

 prism. Transparent or translucent. Lustre 

 viueous. Streak white. Fracture uneven 

 or somewhat conchoidal. H. 7 to 7-5. 

 S.G. 2-6 to 2-7. 



Camp. 3Mg si + Fe Si + 2A12 v;;3 (Qme- 



lin), or if K represent Mg and Fe = K,5 Si^ + 



3A1 Si = silica 49-6, alumina 33-8, magnesia 



8-7, protoxide of iron 7-9 = 100. 



Analysis, from Bodenmais, by Stromeyer : ^ 

 Silica , . . . . 48-33 

 Alumina .... 31-71 

 Magnesia . . . . 10 16 



