Program aims to educate young consumers about mined stones’ positive qualities.
Revenue expected to rise 9% to 11% versus its previous 6% to 10% forecast for the full year.
Move aims to combat rising silver and gold prices.
Consumers are likely to shell out $7 billion on the category before February 14.
X-ray identifies large cavities containing foreign materials.
Three stones in submitted necklace and earrings showed signs of the clarity treatment, lab says.
Revenue from jewelry, watches, clocks and valuable gifts up 14% year on year.
Watches under pressure, with an estimated drop of 14% to 17%.
Revenue up 12% year on year for eight-week period ending December 27.
Rough sales down 38% year on year in fourth quarter.