When shipping a delicate piece, I use spray foam insulation to protect it and keep it from shifting. Styrofoam peanuts can shift in transit, allowing damage to occur, whereas spray foam becomes solid and won’t shift.
I use a can or two of spray foam insulation found in the insulation aisle at my local hardware store. To protect the entire piece and make sure the foam can be easily separated by the recipient, I spray the insulation in two parts.
I first spray a base in the bottom of the box (it will expand, so don’t overdo this step). Once it’s partially hardened, I seal the ceramic piece I’m shipping in a plastic bag to protect it, then press it into the layer of spray foam so that the foam conforms to the piece.
Then, I place another plastic bag over the piece and spray foam into the bag, filling up the remaining empty volume in the box, taking care to fill all the corners and around the piece. Here, the bag makes the foam removable from the box. I sometimes use a bag for the bottom layer of foam so that the entire insulation cushion can be removed from the box.