This is a shit post but was lurking around the web and found this
THE YELLOW PENCIL
Pencils have been painted yellow ever since the 1890s. And that bright color isn’t just so you can find them on your desk more easily! In fact, the yellow pencil has a much deeper history than you might expect.
During the 1800s, the best graphite in the world came from China. American pencil makers wanted a special way to tell people that their pencils contained Chinese graphite.
In China, the color yellow is associated with royalty and respect. American pencil manufacturers began painting their pencils bright yellow to communicate this “regal” feeling and association with China. However, according to Henry Petroski’s history of the pencil, the European producer Koh-I-Noor was the first to introduce a yellow pencil.
https://blog.pencils.com/why-are-pencils-yellow/
https://blog.pencils.com/pencil-history-2/
>Must use a No.2 Pencil to color in those ovals…
…and then there is follow the pen