428 
DESCRIPTIVE MINERALOGY. 
ANATASE. 
[From the Greek, signifying elevated ; in allusion to the height of the pyramids of the octahedral 
crystals.] 
Anatase. Hauij, Bcudant, Phillips and Shepard. — Octaedral Oxide of Titanium. Cleaveland. — Protoxide 
of Titanium. Thomson. — Pyramidal Titanium. Jameson. — Pyramidales Titan-Erz. Mohs. 
Description. Colour blue and brown of various shades ; by trans¬ 
mitted light, it is greenish yellow. Streak white. It occurs regu¬ 
larly crystallized. The primary form is an octahedron with a square 
base. Fig. 510. P on P and P' on P 7 98° 5 7 ; P on P 7 136° 47 7 . 
Cleavage parallel to the primary faces, and perpendicular to the axis. 
Fracture conchoidal, scarcely observable. Lustre splendent and ada¬ 
mantine. Translucent and transparent. Brittle. Hardness from 5.5 
to 6.0. Specific gravity from 3.80 to 3.90. Alone before the blow¬ 
pipe, it is infusible ; with soda, it forms a dull yellow globule, which 
becomes white on cooling. 
Composition. It is supposed to be a pure oxide of titanium. For¬ 
mula TiO. 
Geological Situation. It occurs in small irregular veins in pri¬ 
mitive rocks, as granite and mica slate, where it accompanies albite, 
axinite, quartz, etc. It is still a rare mineral. 
LOCALITY. 
There sometimes accompanies the specimens of native titanium found in the slags of 
Orange county, a coating of a dark blue or purple colour, which may be the oxide of tita¬ 
nium. Although the quantity heretofore observed is quite too small for a chemical examina¬ 
tion, the circumstances under which it is found seem to warrant the opinion which has been 
advanced. 
RUTILE. 
Titane Oxide. Hauy. — Red Oxide of Titanium. Cleaveland. — Rutile. Phillips, Shepard and Bcudant. •— 
Titanic Acid. Thomson. — Peritomous Titanium Ore. Jameson. — Peritomes Titan-Erz. Mohs. 
Description. Colour red, brown, yellow, and sometimes nearly 
velvet-black. Streak pale brown. It occurs regularly crystallized ; 
also massive, disseminated, in angular grains and flakes. Primary 
form a right scpiare prism, Fig. 511. In some crystals the lateral 
edges are replaced by tangent planes ; in others, by two planes. The 
prism is terminated by a four or eight-sided pyramid, and is sometimes 
geniculated and striated longitudinally. Cleavage perfect parallel with 
M ; interrupted parallel with l (see Fig 513). Fracture conchoidal. 
Lustre adamantine, inclining to metallic. Transparent to opaque. 
Fig. 511. 
