Why the World’s Best Mathematicians Are Hoarding Chalk

(via Great Big Story) Once upon a time, not long ago, the math world fell in love … with a chalk. But not just any chalk! This was Hagoromo: a Japanese brand so smooth, so perfect that some wondered if it was made from the tears of angels. Pencils down, please, as we tell the tale of a writing implement so irreplaceable, professors stockpiled it.