Luster refers to the appearance of the reflection of light from a mineral’s surface. It is generally broken into two main types: metallic and non-metallic. Minerals with a metallic luster have the color of metal, like silver, gold, copper, or brass (Figure 7.14). While minerals with a metallic luster are often shiny, not all shiny minerals are metallic. Make sure you look for the color of metal, rather than for just a shine. Minerals with non-metallic luster do not appear like metals. They may be vitreous (glassy), earthy (dull), waxy (similar to a candle’s luster), greasy (oily), or other types (Figure 7.15).