I'm not sure if I'm looking at a true fossil, or is this an impression of a modern day plant. As I often do, I washed the fossil down with warm water three times with the hope that if it was a modern imprint, it would partially, or completely fade away. Since it didn't fade one bit, I would like to please ask if these plant impressions are indeed legit fossils, or a stubborn modern day imprint. Early Jurassic, East Berlin Formation of Connecticut, USA. Thank you!