The previous FTC definition described a diamond as “a natural mineral consisting essentially of pure carbon crystallized in the isometric system.” However, the word “natural” has since been removed.
The FTC explained, “The Commission no longer defines a ‘diamond’ using the term ‘natural’ because it is no longer accurate to limit diamonds to being ‘natural’ when products can now be created that possess essentially the same optical, physical, and chemical properties as mined diamonds.”