SUBSILICATES, 281 
tolite, euclase, and part of staurolite, hydrogen, that is, the 
hydrogen of the water found on analysis. In chondrodite, 
topaz, and some tourmaline, fluorine replaces part of the 
oxygen. 
Chondrodite.—Humite in part (Scacchi’s Type II). 
Monoclinic. Cleavage indistinct. Usually in* imbedded 
grains or masses. Color light yellow to brownish yellow, yel- 
lowish red, and garnet-red. Lustre vitreous, inclining alittle 
to resinous. Streak white, or slightly yellowish or grayish. 
Translucent or subtranslucent. Fracture uneven. H.=6- 
Ora) -Gue=o 1-325. Ge 
Composition. Mg, O,,Si;; but a portion of the magnesium 
replaced by iron, and a part of the oxygen by fluorine. A 
specimen from Brewster’s, New York, afforded Silica 34:1, 
magnesia 53°7, iron protoxide 7:3, fluorine 4°2, with 0°48 of 
alumina= 99°72. 
B.B. infusible. Decomposed by hydrochloric acid ; the 
solution gelatinizes on evaporation. 
Diff. As it cceurs only in limestone it will hardly be con- 
founded with any species resembling it in color when the 
gangue is present. It does not fuse like tourmaline or gar- 
net, some brownish-yellow varieties of which it approaches 
in appearance. The name is from the Greek chondros, a . 
grain. 
Obs. Itisabundant in the adjoining counties, Sussex, N. J., 
and Orange, N. Y., occurring at Sparta and Bryam, N. J., 
and in Warwick and other places in N. Y.; at the Tilly 
Foster Iron Mine, Brewster’s, Putnam County, N. Y., it is 
very abundant. At Vesuvius it occurs in small crystals. 
The species was early named Chondrodite, from Finland 
specimens ; soon afterward small crystals, found in the lavas 
of Somma (Vesuvius), were named Humite, and both were 
referred to the same species. It has recently been ascer- 
tained that under this species, two species of different an- 
gles and form, but related composition and physical charac- 
ter, are included. For these species the names Humite and 
Clinohumi‘e have been adopted. | 
Humite is orthorhombic, and embraces part of the Humite 
crystals of Vesuvius (Scacchi’s Type I.), and some large 
coarse chondrodite-like crystals found at Brewster’s, N. Y. 
Clinohwmite is monoclinic, and includes Seacchi’s Type III. 
