Gemstones of Nigeria: An Overview of Their Geological Occurrence, Provenance and Origin

Abstract

Gemstones are a special class of industrial minerals that are cut or faceted and polished for use as jewelry and other personal adornments. Gemstones are adorable objects that are desired and sought after by both royalty and the wealthy for their unique properties including beauty and color, luster and sparkle, durability and hardness, and extreme rarity. Gemstones, on the other hand, are minerals that constitute part of a country’s natural endowment to be explored, exploited and revenues used for community benefit. Nigeria is endowed with substantial gemstone resources and the only country in Western Africa with commercial deposits of precious and semi-precious stones including Paraiba tourmaline, sapphire, emerald, aquamarine, spessartite and rhodolite garnets, beryl, topaz, amethyst, zircon, and a couple of rare species such as ruby, phenakite, kunzite, tanzanite, tsavorite and lepidolite. Most of the gemstones are mined mostly “informally” from weathered rocks and associated eluvial and alluvial deposits by artisanal and small scale miners who are virtually illiterate individuals who sell their raw gems for quick cash with no value added. There are no records of production, and little or no revenue gets into the Federal Government coffers. This paper presents an overview of the geological occurrence, distribution, provenance and origin of Nigerian gemstones, and the potential application of the knowledge in gem prospecting and exploration. There is an urgent need for government reforms of artisanal mining and active regulation of the gemstone industry so that all the loopholes and leakages in the gem supply pipeline and value chain are fixed for the utmost benefit of the Nigerian economy.