This issue only happens to a few blocks, but is consistent with an iron block.

What happens is essentially whenever I attempt to chisel an iron block, when I place said chiseled block it reverts to: Block of Iron (Caution).

Pictures below to demonstrate.

https://imgur.com/a/Ho2zj

I can left click the block in the world and change it just fine, but using right click function to chisel creates this glitch, it happens with iChisel too.

The pack I play with is 1.12.1

Can you still reproduce this?

The same thing happens for me, but with the Quark Polished Marble block. If I pick Polished Marble from Quark, it give it to me, but when I place it, it turns into Chisel:Marble_Raw.

I know we have that problem with using UniDict in the same pack so it's unifying all the iron so if it's chiseled, it changes to the unified default. We're trying to also find a workaround. I assume the chisel blocks need to be in the OreDictionary to work?

Yes, the oredict is required.

Thought so! Just wanted to confirm for my sanity! :)