Marble is a type of stone used in sculpture. Marble is very expensive and harder than many other stones.
For the beginner or artist on a budget, thousands of artists use a variety of different stones, not to mention wood, plaster, concrete, various metals, papier-mâché, polymers, and found ibjects.
For large, classic stauary bronze and marble are extremely common.
Reinforced vinyl tarps sewn together with the seams then sealed using a vinyl repair adhesive can take a heck of a beating.