[nwhitehead]

In my mind the real tragedy is blackboards. Almost nowhere has good blackboards anymore except for math departments in older universities that stubbornly refuse to replace their old boards. Since the 1970s everything has been replaced with inferior materials.

[scott_karana]

What makes for a good blackboard? Could they be reproduced?

[nwhitehead]

The old good ones are heavy, dark, and silky smooth. The new ones are lighter, noisier, have more friction, and erasing leaves more of a mess (in my opinion). Reading online people say that the old slate ones were harder to erase and had glare problems. I agree with the glare, the old style boards do show glare from sunlight coming in from side windows which is annoying.