Best tool steel to use on passivated or EP parts

[quizzical1]

Hi All,

We are currently using O1 anvils to crimp parts together which i know could leave iron deposits which defeats the passivation / EP.
We are considering switching to D2 but was wondering if there's a better choice?

TIA

Q~

 

[TugboatEng]

Before retooling your process, consider using a pickling paste to touch up any contaminated surfaces.