The copper block is missing its oredict entry for compatibility with other mods.
Another issue is that it's not named like all other metal blocks:
"Block of [metal]" vs "Copper Block"

Forge 12.16.1.1990
RebornCore-1.9-2.3.2.84-universal.jar
TechReborn-1.9-1.1.1.267-universal.jar