Polissoirs de Coinche, Prehistoric grooves in Chantecoq, France.

Polissoirs de Coinche is a Neolithic site in Chantecoq, Loiret, made up of a menhir and two fixed polishing stones of fine Ypresian sandstone. The larger stone, to the south, carries three parallel grooves, five basins and a polishing surface; the second has only three partial basins. The menhir is a puddingstone block 1.60 m high, 1.40 m wide at the base and 70 cm thick, pierced almost through its centre.

The site dates to the Neolithic period. The menhir and two fixed polissoirs were classified as a monument historique in 1986. A third, portable polissoir was found near the menhir in 1982.

The site shows how early inhabitants of the area shaped and refined their tools through daily work. These stones stand as evidence of practical skills passed down through generations of craftspeople.

The stones are located in an open outdoor setting and are accessible at all times. Sturdy footwear is recommended, as the terrain can be rough and uneven.

The largest of the two fixed polishing stones carries three grooves, five basins and a polishing surface; the second has only three partial basins. The grooves run lengthwise across the pale grey stone, which is mottled with green lichen and rests on bare earth.