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The chalk mathematicians adore: Hagoromo Fulltouch Chalk

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Mathematicians have called it “one of the best-kept secrets in the math world,” dream chalk, legendary, and the Michael Jordan and the Rolls Royce of chalk. Professor Satyan Devadoss even said that “with Hagoromo chalk, the math practically writes itself.”

Great Big Story looks into the Chalk of Champions: Hagoromo Fulltouch Chalk. Made in Japan for 80 years before Hagoromo Bungu closed up shop in 2015, this chalk was revered by mathematicians and chalk artists alike. People were stockpiling it and rationing it “for use only during their most important lectures or when working on their most important theorems.” So why Hagoromo Fulltouch Chalk? Jeremy Kun explains:

Hagoromo chalk writes as smoothly as butter. It shines. It’s bold, sturdy, clean, and erases well. A single stick of Hagoromo lasts for at least four lectures. Some of my colleagues were initially skeptical, but once they started using Hagoromo regularly and tried to go back to their old chalk, the difference shocked them.

Some of the reasons included its thickness, texture, and the wax coating that kept fingers and clothes clean. Hagoromo’s last president, Takayasu Watanabe, spoke with pride about their chalk-making machines to Nikkei Business:

Manufacturers do not produce machines for making chalk. We had to do that ourselves. I developed the production facilities by trial and error with a managing director who retired a while ago. For creating the materials for chalk, we modified a machine for mixing flour. For molding the sticks of chalk, we tweaked a machine for making roof tiles.

The machines, which we continued to modify over more than 20 years, felt like our children…

One of their three machines stayed in Japan with the company Uma-jirushi. Two went to South Korea. Sejongmall now produces the original formula under Japanese Industrial Standards. You can find it on Amazon.

Watch these next: Pardon My Dust – Dynamic Sketching with Peter Han and the intricate, temporary chalk animals of Philippe Baudelocque.

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