The artist’s needs, plus the size, shape and complexity of the sculpture often define the material choice. The most economical choice is to use a light weight, low-density foam. The foam enlargement can have up to 95% of the surface detail. A thin layer of clay, wax or plaster is then applied over the entire surface of the foam armature. The final fine surface detail is then captured in the thin layer of clay, wax or plaster by the artist.
If the artist wants to try to limit their work on the enlargement by capturing more details in the armature, then denser materials are required and more time is needed in the milling process, however this obviously increases costs.