St. Mary's Church, Old Amersham

To meet today's challenge of bricks or stones I picked this church, built in the 13th, 14th and 15th centuries. In 1870 the exterior was clad with knapped flint. (See extra) The flint was probably locally available as the thin chalk soil contains flint stones.
Knapped flint were quarried from the chalk beds so the exterior has a white chalk crust. The raw flints were split (knapped) to expose the glossy dark centres,