freestone

noun2

1. •
   A stone fruit having a stone (pit) that is relatively free of the flesh.
2. •
   Sedimentary rock: a type of stone that is composed of small particles and easily shaped, most commonly sandstone or limestone.

   • Mr Allworthy […] died immensely rich and built an hospital […] but had he done nothing more I should have left him to have recorded his own merit on some fair freestone over the door of that hospital. — 1749