Here is a picture of an ammonoid fossil found at Basilica di Santa Croce in Florence, Italy. This building material is a iron enriched (red) limestone also known as
Red Verona marble or Rosso Verona marble used in a lot of churches
including this one. The material dates to the Upper Jurassic
Period of the Rosso Ammonitico Formation, Oxfordian Stage, Verona
Province, Venetia Region of Italy. Pictures taken August 2024.