Galena Crystal Specimens #2 Galena is the natural mineral form of lead sulfide with a distinct silver color and a bright metallic luster. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms Galena is the most common mineral containing lead, and has been well-known throughout the centuries. many crystals are found somewhat in-between octahedral or cubic-octahedral crystal forms, resulting in bizarre and interesting shapes. Galena specimens may tarnish in time, becoming dull in luster. Freshly cleaned specimens exhibit a strong metallic luster, but over time the luster turns more dull, while still metallic.