What Polish Definition is a Lego Brick?

Skills materials and processes
2

Hope this helps.

http://www.professional-plastic-mold-manufacturer.com/knowledge-advice-plastic-injection-molding/spi-mold-finish-practical-approach/

Without looking at samples, Legos I would imagine are (just guessing):

SPI Finish A3 – 718H or S136 Hardness 32HRC
(Generally called “Normal Glossy” in China)

Good luck.