Cassiterite vs Rutile
| Property | Cassiterite | Rutile |
|---|---|---|
| 化学式 | SnO2 | TiO2 |
| 晶系 | Tetragonal | Tetragonal |
| 矿物分类 | 04 Oxides and Hydroxides | 04 Oxides and Hydroxides |
| 莫氏硬度 | 6.0-7.0 | 6.0-6.5 |
| 颜色 | Brown, black, reddish-brown, yellow | Reddish-brown, red, black, golden |
| 光泽 | Adamantine | Adamantine |
| 条痕色 | White to pale brown | Light brown |
| 透明度 | Translucent | Translucent |
| 解理 | Poor {100} | Good {110} |
| 断口 | Subconchoidal to uneven | Conchoidal to uneven |
Key Differences
- ◆ Rutile (TiO2) is the primary titanium ore; cassiterite (SnO2) is the primary tin ore — both are tetragonal dioxides.
- ◆ Cassiterite (specific gravity 6.8–7.1) is significantly denser than rutile (4.18–4.25).
- ◆ Rutile forms golden to reddish-brown needle-like (acicular) crystals; cassiterite forms bipyramidal prismatic crystals.
- ◆ Rutile commonly occurs as inclusions in quartz (rutilated quartz) and as the 'silk' in star sapphires.
- ◆ Both are found in placer deposits due to their resistance to weathering.