These are made out of plaster of paris you can by it at your local hardware store, here is a link www.michaels.com/product/dap-plaster-of-paris-10515940?cm_mmc=PLASearch-_-google-_-MICH_Shopping_US_N_Craft+%26+Hobbies_N_PMAX_BOPIS_N-_-&Kenshoo_ida=&kpid=go_cmp-18514199759_adg-_ad-__dev-c_ext-_prd-10515940&gad_source=1&gclid=Cj0KCQjwn9y1BhC2ARIsAG5IY-5lIsU6evpvXAMswhjHEIO0z5Anea0NtnShY-1e5QjphpGZ_quu1YwaArOREALw_wcB
