The center is a core of Corning insulation foam. Once that was sanded just smaller than the hoped-for model, I covered it with an air-drying clay called "Makin's Clay" that I found at my local Michael's.
The fins, lips etc were made from Magic Sculp.
(Makin's Clay does not take detail as well as MS. And it stays fairly soft for days.)
The squid is held aloft by coathanger wire running through the left forward fin.
The other fins have wire reinforcing them as well.
The rocks are either MC or MS supplemented with aquarium gravel.
It was a fun build!
![Big Smile [:D]](/FSM/CS/emoticons/icon_smile_big.gif)
-Leelan