The “Gate of Paradise” glasses comprise two drop-shape, flat-cut emeralds weighing a total 27 carats set in silver and gold frames mounted with old-cut diamonds and emeralds. The lenses are approximately 2.6 cm x 2 cm x 0.295 cm.
Then there’s the “Halo of Light” spectacles, crafted with two flat-cut diamonds weighing 25 total carats set in silver and gold frames mounted with smaller old-cut diamonds. One lens is about 2.5 cm x 2.3 cm x 0.159 cm; the other approximately 2.4 cm x 2.2 cm x 0.171 cm.
Each pair is estimated to sell for between £1.5 million and £2.5 million (about $2.1 million to $3.5 million) at the sale, where they are being offered for the first time.
The spectacles originated in 17th century Mughal India, where they were commissioned by an unknown prince, according to Sotheby’s.
An artist shaped a diamond weighing more than 200 carats and an emerald weighing at least 300 carats into the two creations.
Sometime around 1890, the lenses were placed into new frames, decorated with rose-cut diamonds.
And though the original patron of these pieces is unknown, the quality of the gemstones combined with their sizes suggest they “would no doubt have been in the reserve of an emperor.”
The teardrop-shaped emerald lenses originated from a single natural Colombian emerald, beveled at such an angle to preserve the intense color of the original stones.
The diamond lenses used in the other pair were cleaved from a single stone believed to have come from the famed Golconda mines in southern India.
The faceting around the edges of the diamond lenses took extreme skill, arranged to preserve transparency while also releasing light from the edges, Sotheby’s said.
Adding to the skill needed to craft such pieces is the lore and mythology behind them.
Where ordinary lenses aimed to improve sight, these filters were created to aid in spiritual enlightenment—diamonds were thought to illuminate, and emeralds were believed to have the power to heal and ward off evil.
Pliny the Elder provided the most famous—and likely earliest—example of such glasses in his work, “The Natural History,” dating from the Roman Empire, which recounts Emperor Nero watching the gladiator contests through a precious green stone.
Much later, the treasure of Charles V of France included a case of beryl stones framed as spectacles.
Watch: An Expert Talk About the Mughal Spectacles
Sotheby’s said Gate of Paradise and Halo of Light are believed to have been in the same collection for nearly half a century.
“These extraordinary curiosities bring together myriad threads—from the technical mastery of the cutter and the genius of craftsmanship to the vision of a patron who chose to fashion two pairs of eyeglasses quite unlike anything ever seen before,” said Edward Gibbs, chairman of Sotheby’s Middle East & India.
“They are undoubtedly a marvel for gemologists and historians alike, and it is a real thrill to be able to bring these treasures to light and to offer the world the opportunity to wonder at their brilliance and the mystery behind their creation.”