Hi everyone: I recently purchased a Zenith pro boar brush and after a two week break in session took it out for a spin with a shave. After clean up I noticed what looks like tarnishing or staining on the handle, see pic below. Seems so strange this would happen after just one use... Perhaps from my preshave or shaving cream? (I usually use Proraso preshave and Muhle cream) Had a look online and it seems one can just use any aluminum polish like Mothers etc but wanted to check in with the forum and see if anyone has had a similar experience or feedback with cleaning up an aluminum handle? Thanks so much!