South London Branch member, Antonio Silva, sent these pictures of a carriage clock with savage two-pin lever escapement that had been on his bench recently. When he started to dismantle the platform escapement, he was surprised to find a red powdery deposit that had built up around the balance staff and lever. At first he thought it might be polishing compound such as rouge.
On closer inspection it turned out that one of the two pins on the roller had been replaced with a polished steel pin and through constant contact with the steel lever had worn and the subsequent dust had oxidized into powdery rust.
The pins on the Savage escapement were usually gold and do wear and so it is normal to see replacements but, from this example, it is clear that steel replacements are not a good idea.