pigment liner, and the background dots are sharpie.
The teapot: https://www.metmuseum.org/art/collection/search/197991 2 very similar 1760's teapots: https://blog.mam.org/2011/08/31/objects-in-focus/ Some examples of crinoidal limestone so you can see what the original teapots were inspired by: https://natmus.humboldt.edu/mississippian-polstn https://www.dreamstime.com/stock-photo-crinoidal-limestone-image14180620 https://i.etsystatic.com/19287901/r/il/590818/2972540118/il_680x540.2972540118_lpl4.jpg