Occasionally, there is something new under the sun or, in the case of a beautiful new gem called Royal Lavulite, under the earth. The deep translucent purple stone, known to mineralogists as sugilite, was officially classified as a rare gem in October 1980, and prices for the stone quickly climbed to as much as $1,000 a carat, compared with $3,000 to $5,000 a carat for the finest grade commercial diamonds.
Sugilite has been found in Japan and India, but only in small deposits that were not of gem quality. In August 1980, workers in a manganese mine in South Africa first discovered...