Dry aged beef - HELP

[Throughabushbackwards]

Aged beef virgin here -

Wonder if someone might be able to tell me if this piece of forerib is ok? It's aged, but can't recall how many days. We have scraped some white mould off the outside of it but are paranoid about black and green mould! The butcher was lovely explaining how to look after it and prepare it, but he has made us slightly nervous

It doesn't smell at all BTW.

Very hot oven 220 then turn down for 20 mins per kg

Go see nigella for the timings for rare medium etc
Good luck

Its meant to be like that!

Thank you both for the reassurance! Enjoy your day tomorrow.