To add on to this, if a material with a lower hardness cannot damage a material with a higher hardness, then we wouldn’t be dinging our yoyos already. In fact, walking the dog on concrete will leave your yoyo in pristine condition! No marks or dings at all, because concrete has a mohs hardness rating of 5-7 and aluminium oxide has a mohs hardness rating of 9. But, that is not reality (we do wish that was reality don’t we?)
@craZivn I suggest reaching out to yoyofactory about this, it’s not usual. I’m pretty sure they’ll provide you with a replacement that won’t have this problem as this issue is pretty rare (but very difficult to test for).
Here are a few threads about similar issues with other yoyos: