So what's the truth of the hardness/blackness grade? Did Conte invent it? Because Hardtmuth, one of the large pencil manufacturers, claims otherwise: "Accordin

So what's the truth of the hardness/blackness grade? Did Conte invent it? Because Hardtmuth, one of the large pencil manufacturers, claims otherwise: "According to the personal notes of Franz Hardtmuth, the marking of pencils using the letter H originates from the family surname Hardtmuth, B means Budweis, or Budějovice in Czech language, and F refers to his first name Franz." https://www.blog.koh-i-noor.cz/post/the-story-of-iconic-koh-i-noor-graphite-pencils?lang=en https://www.blog.koh-i-noor.cz/post/the-story-of-iconic-koh-... Sounds a bit apocryphal to me.