Issue description:
Currently a draft while I pinpoint patterns in how this issue manifests to help diagnose a root cause. The issue affects multiple mods. For example, an Immersive Engineering ore block may drop Apatite ore from the Forestry mod.
Versions:

• Minecraft: 1.12.2
• Forge:
• Mantle:
• Tinkers Construct:

Can it be reproduced with just Tinkers Construct? If not, list the other mods required to reproduce the issue.
I'm experiencing the issue with the Engineer's Life modpack.

You probably have a mod like unidict installed to unify the ore drops, maybe is working incorrectly. All our silk touch tools do is give you vanilla silk touch.

UniDict is not installed, would a mod like CraftTweaker be capable of causing an issue like this?

Silktouch is quite literally vanilla silktouch. Have you tried if the same happens with vanilla pickaxes that are silktouch enchanted?

Closing for lack of response, our code just uses vanilla logic