Physical Properties |
|
| Chemical Formula | TiO2 |
| Class | Oxide |
| Crystal system | Tetragonal |
| Habit | Massive Stubby to acicular tetragonal crystals Striated prismatic crystals |
| Color | Red Red-brown to black |
| Hardness | 6 to 6.5 |
| Specific gravity | 4.24 |
| Cleavage/b> | Good prismatic {100} and {110} |
| Fracture | Subconchoidal |
| Luster | Adamantine Submetallic |
| Transparency | Transparent to translucent |
| Streak | Pale or light brown |
Optical Properties |
|
| PPL | Deep red, red-brown, or yellow-brown Very high relief |
| XPL | 3rd order colors |
| δ | 0.29 |
| Twinning | Common |
| after Perkins, 370 |
Rutile in Thin Section
Rutile (it’s the tiny black grain)
Rutilated quartz with ilmenite
Scanning electron micrograph of rutile needles (lighter color) exsolved on biotite
Rutile in Thin Section
Thin Section GigaPans
Rutile in plane polars
Rutile in crossed polars
