Is there a block that a Turtle can't break?

Hello,

I play on a modded war-themed server that includes Computercraft. Someone mentioned a strategy of sending turtles through someone's base to destroy their storage rooms and steal all their stuff. To protect against this, I'm wondering is there any survival-obtainable block in any mod (we'll add it if we don't have it) that a Turtle can't mine. Something that just stops it dead there.

Thank you,
Republican31

Warded blocks from the likes of Thaumcraft are probably your best bet, though I know RotaryCraft allows the mining of bedrock.

RFtools have a type of block protection and also shield blocks you can test.

Edit: I thought I try to test breaking shield blocks with a turtle but I could not start my game after updating to java 8 update 91…