The Weekend in Black and White

This diamond (part of an exhibit at the
Metropolitan Museum of Art that I showed you
 on Tuesday) is actually quite new—made by Cartier
 in 2013.  Its name, the Star of Golconda, alludes to a
kingdom in India from which the Koh-i-noor
and Hope diamonds came.

[To see more monochromes, visit Dragonstar's meme.]