Freestone (masonry)
A freestone is a stone used in masonry for molding, tracery and other replication work required to be worked with the chisel. The freestone must be fine-grained, uniform and soft enough to be cut easily without shattering or splitting. Some sources[who?] say that the stone has no grain, but this is incorrect. Oolitic stones are generally used, although in some countries soft sandstones are used; in some churches an indurated chalk called clunch is employed for internal lining and for carving. Some[who?] believe that freemason originally meant one who is capable of carving freestone.
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This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). Encyclopædia Britannica (11th ed.). Cambridge University Press.