{Request} help with mechanics of reformation crystals!

I'm trying to figure out the general workings of reformation,specifically reformation or revival crystals,for an upcoming RP me and another redditor are waiting on. I know the basics of reformation,but can't remember the finer details,like if you have to swallow the object used for the revival/reformation down with your prey or not. I am still new to being a pred,normally I'm a switch(can't figure out the dang lable thingy on here tho) useually,but in this instance I'm preparing to settle a larger prey in my belly,but I want to reform them so I don't feel terrible about melting someone down,even if they become part of me forever. Any tips would help and be greatly appreciated,Thank you!