Cement filled block

I am a chemist.

Tough call on this one.

Acids: Hot concentrated Nitric Acid or Sulfuric Acid can be used but it will damage the block by removing/dissolving metal.

Solvents: you would have to determine what type of resin it is. I imagine that it is probably an epoxy which means it would take a combination of toluene, acetone, and probably methyl-ethyl-ketone just to soften it up. It would probably need to be heated to have any affect. You would need to be in well ventilated area and be away from any flames or ignition sources. Oh, and don't breathe the fumes.

Heat: you might be able to burn it off but then you would have to be careful about localized heating of the metal in the area of the flame.