freestone

Concise Oxford English Dictionary © 2008 Oxford University Press:
freestone/ˈfriːstəʊn/

▶noun

• 1 a fine-grained stone which can be cut easily in any direction, in particular a type of sandstone or limestone.

• 2 a fruit in which the stone is easily separated from the flesh when the fruit is ripe. Contrasted with clingstone.