I just bout this rock from a pet store. The rock seems to be clay based. Is this safe for my bearded dragon to bask on? Im scared it might stain his feet over time, but I see a lot of people make rocks out of clay for their dragons. I need some input. Thanks.
It's probably fine, especially if it's set clay. Can you post some photos or provide a link? You can upload photos here https://www.beardeddragon.org/useruploads/ and post them to your thread using the XIMG button.
Polyurethane would probably seal it better but requires a lot of time to set thoroughly in a well ventilated area. It's probably not necessary to seal it but if you're concerned about moisture and bacteria buildup it's not a bad idea.