Geographic Origin Determination of Ruby

GEMS & GEMOLOGY WINTER 2019 The world ruby market has changed dramatically in modern times, especially in the last decade with the discovery and development of ruby mining in Mozambique (Chapin et al., 2015). As the gem trade has witnessed turbulent and dramatic changes in the ruby supply chain, the concept of geographic origin has become increasingly important to people buying and selling fine rubies. Often, the origin of a ruby plays an important role in the value placed on the stone, especially for exceptional quality rubies from Myanmar (figure 1). As with other colored gemstones, the ruby trade relies to a large extent on reputable gemological laboratories to make these origin determinations. In the second material-specific article of this series we delve into the world of rubies, their gemological properties, and characteristics that may aid in geographic origin determination. The following sections will detail the origin data GIA has collected for rubies and describe the methodology used in the lab to apply this data to geographic origin work.