Spodumene once served as the most important ore of lithium metal. It was very costly to liberate lithium from the silicate mineral; however, lithium refined from spodumene was of very high purity. In the late 1900s, subsurface brines with high concentrations of lithium were developed in Argentina, Chile, China and other locations. These brines could be pumped to the surface, allowed to evaporate, and lithium was easily processed from the evaporite material.
As lithium-rich brine deposits were developed, the more costly use of spodumene as an ore of lithium declined. At times, the demand for lithium has exceeded what can be produced from working brine deposits. In those times spodumene can become an important source of lithium metal.
| Physical Properties of Spodumene | |
| Chemical Classification | Silicate |
| Color | White, gray, colorless, yellow, green, blue, lilac, pink, brown. Sometimes pleochroic |
| Streak | White, colorless |
| Luster | Vitreous, pearly |
| Diaphaneity | Transparent to translucent |
| Cleavage | Perfect in two directions with parting |
| Mohs Hardness | 6.5 to 7 |
| Specific Gravity | 3.1 to 3.3 |
| Diagnostic Properties | Prismatic crystals with strong striations parallel to their principal axis. Perfect cleavage. |
| Chemical Composition | LiAl(SiO3)2 |
| Crystal System | Monoclinic |
| Uses | Gemstones (kunzite, hiddenite, triphane). Once the most important source of lithium metal. |