These developments in gem diamond identification
have introduced many scientific terms and concepts
into the gemological literature. One of the most
important of these concepts is diamond “type.” The
diamond type classification system is widely used in
diamond research, because it provides a convenient
way to categorize diamonds based on their chemical
and physical properties. Understanding this system is critical to evaluating the relationships between diamond
growth, color (e.g., figure 1), and response to
laboratory treatments. With the increasing availability
of treated and synthetic diamonds in the marketplace,
gemologists will benefit from a more complete
understanding of diamond type and of the value this
information holds for diamond identification.