While blackstone and cobbled deepslate can still be used to substitute cobblestone for crafting stone tools and furnaces, it cannot be used as a substitute for observers, pistons, droppers, etc.
MC-263666
Blackstone, Cobbled Deepslate Can't be Used in Some Recipes
Resolved
Duplicate
0
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We're tracking this issue in MC-177904, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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