@chikara didn't know the japanese used it, or that Lead oxide has these colors.. Not surprising they used it because relatively convenient paints for all the different colors is relatively new.

Btw, though searching, i find people basically hating on Thomas Midgley. On the other hand, did see an article once basically talking about him has blundering into his disasterous inventions. But no doubt, they knew, they were told, repeatedly.

@jasper Thanks for the feedback, especially because you drew my attention to Thomas Midgley -- see Wikipedia "Thomas Midgley Jr." https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.; and see "List of inventors killed by their on inventions"
https://en.wikipedia.org/wiki/List_of_inventors_killed_by_their_own_inventions

SOCIAL MEDIA VENUE. If I understand correctly, QOTO is a social media venue; and -- tbh -- the underlying intent in each of my posts is social.

Think about it: In each post, I'm only working though a half-baked idea sparked by something small. And I'm looking for any kind of feedback that might help me find ways to move outside the box of my own thinking.

OUTSIDE-THE-BOX QUESTIONS. With each post, I'm sharing a work-in-progress, asking questions with a bit of a STEM-related twist. And I'm bringing together a few hyperlinks that establish a wider foundation for more outside-the-box questions.

In response, your words have sparked questions and suggested additional research topics. Good. I'm grateful

@chikara for me it's an inside the box question, but glad i could contribute.

I generally like you're promiting the idea of researching, but think finding out how reality works is such a tricky thing.. Ah well, just do our best..

@jasper Thanks for the "tbh"

Your acronym was new to me, so I googled it. I liked learning about the evolution of nuance as explained in the featured snippet-- see "'Tbh' no longer just stands for 'to be honest' on Instagram" (Nina Godlewski). Business Insider. May 27, 2016. https://www.businessinsider.com/what-does-tbh-mean-2016-5