Metal transfer marks 101 Cleaning and caring for your Oura Ring 4 Ceramic

https://www.reddit.com/r/ReviewJunkies/comments/1p4ulug/we_tried_the_oura_ring_4_ceramic_track_50_health/

Anyone who’s worn rings knows metal transfer marks are sneaky guests on your jewelry. Here, we focus on how these marks affect ceramic smart rings and the best cleaning methods to erase them without scratching your Oura Ring 4 Ceramic