The relationship that builds between the pair is a slow burn sparked during small ordinary moments where they perform daily tasks together or walk along the beach where Mary hunts for rocks containing fossils such as the titular Ammonite. Drawing aloof, guarded Mary out of herself is not an easy process and could be compared to the delicate operation of extracting fragile fossils from the inflexible rocks. This is played well by Winslet who treads the line between being withholding and simply being cold. I felt we were drawn into Mary’s emotional landscape well the more we got to see her interactions with her mother (played by Gemma Jones) and a gardiner who seems to be an ex of Mary’s played by Fiona Shaw.
Where Ammonite fell down for me was that I didn’t feel we got to know Charlotte very well. A few more scenes spent with her and Fiona Shaw’s character or maybe even showing her setting everything up before Mary comes to visit towards the close of the film would have made me feel more connected both with her as a character and the story as a whole. The way the film ended left me with the impression of having witnessed an unfinished conversation and while it’s not the worst to be left wanting more, I felt a little betrayed!
That said, I do have a major affection for Francis Lee’s filmmaking approach and the bright stark light of the beach contrasting with the grey sparkled rocks and all of the grey, desaturated cold setting that these characters exist in is really gorgeous. The reticent use of sound mirrors Winslet’s withholding portrayal of Mary Anning. There is a lovely moment where she plays the piano for Charlotte that gives us a subtle understanding of these two characters and their dynamic. 
(2.5 / 5)