Quickly, someone figure out how deep slate is!
If you move more than 999999 TU away from the center, it'll start getting really glitchy. Thus, if you use that as size, it's 3999996 (in plates, 19999980) bricks deep (from top to bottom, not from what you stand on). In total, the non-glitchy area of Slate can contain ~63999808000192 + 10
19 bricks
3. If we counted plates instead, the number would be ~31999904000096 + 10
20 bricks
3.