As far as I know these were the first Christian Dior sunglasses made of optyl, the miracle resin that was supposed to supplant cellulose acetate. They date from about 1969.
Wilhelm Anger, the inventor of optyl had taken over the Dior license from Tura in 1966. Optyl apparently wasn’t ready for commercial production yet, so the earliest Austrian-made Dior sunglasses were actually made of acetate.
The U.S. made eyeglass frames Tura produced had been great; in their own way more interesting than the wonderful designs Anger’s company would churn out through the 1970s and 1980s. Tura had produced eyeglass frames that were highly original; really pieces of jewelry in their sensibility. Some were even available with matching bracelets. In contrast Anger’s first Dior sunglasses had a more modernist look. The fact the frames were molded (or cast) allowed a more extensive vocabulary of curves, planes and angles.
For the first Dior frame made of optyl, though, Anger’s design team hearkened back to a flashy magnificence reminiscent of Tura’s Dior line. A stamped metal plate with an enamel-like pattern suggestive of paisley is mounted on a large, round, very thick optyl frame.
Thus the beginning of the optyl era was announced with an exclamation mark.