Eolith
An eolith, meaning "dawn", and λίθος is a flint nodule that appears to have been crudely knapped. Eoliths were once thought to have been artifacts, the earliest stone tools, but are now believed to be geofacts.
The first eoliths were collected in Kent by Benjamin Harrison, an English amateur naturalist and archaeologist, in 1885. Harrison's discoveries were published by Sir Joseph Prestwich in 1891, and eoliths were generally accepted to have been crudely made tools, dating from the Pliocene. Further discoveries of eoliths in the early 20th century - in the Red Crag Formation and Norwich Crag Formation of East Anglia by J. Reid Moir and E. Ray Lankester and in continental Europe by Aimé Louis Rutot and H. Klaatsch - were taken to be evidence of human habitation of those areas before the oldest known fossils. The English finds helped to secure acceptance of the remains of Piltdown Man.
Because eoliths were so crude, concern was raised that they were indistinguishable from the natural processes of erosion. Marcellin Boule, a French archaeologist, published an argument against the artefactual status of eoliths in 1905, and Samuel Hazzledine Warren provided confirmation of Boule's view after carrying out experiments on flints.