Why the World’s Best Mathematicians Are Hoarding This Chalk

While mathematics may contain the secrets of the universe, the world’s best mathematicians have been particularly interested in the secret behind this chalk formula.

Professors and educators around the world have been hoarding a certain kind of Japanese chalk that was previously made by a company called Hagoromo. It was so highly prized by mathematicians they referred to it as “the Rolls-Royce of chalk.”

Most people are still mystified by the recipe and techniques that were used to make the utensils, but one professor said he assumed the secret ingredient was “angel tears.”

Hagoromo made chalk for more than 80 years, and for those who weren’t lucky enough to live in Japan, Fulltouch was always difficult to get. Then, as Hagoromo prepared to shut down in 2015, many dedicated aficionados began grimly preparing for a world without Fulltouch.


After Hagoromo went out of business, teachers desperately started hoarding the chalk and trading it like precious jewels.

Thankfully, a Korean company bought the chalk recipe from Hagoromo and continued making the sticks – but listening to educators talk about their longtime romance with the chalk is still priceless.

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.