16 cm Septarian ammonite bed with Promicroceras and others, from Charmouth beach

A beach worn pebble measuring 16 cm across filled with Promicroceras and Cymbites ammonites with calcite septarian cracks. The face of the nodule has been polished to a high shine. 
 
No repairs or restoration, 
The piece originates from the Stellare Septarian nodule bed. 
 
Lower Sinemurian, Black Ven Mudstone Member, Charmouth Mudstone Formation, Charmouth, Dorset. 195 MYA