PARIS — King Richard I, the 12th-century warrior whose bravery during the Third Crusade gained him the moniker Lionheart, ended up with a heart full of daisies, as well as myrtle, mint and frankincense.

Those were among the findings of a French study, announced Thursday, which analyzed the embalmed heart of the English king more than 810 years after he died.

The biomedical analysis also uncovered less flowery and spicy elements like creosote, mercury and perhaps lime in the heart, which has been in the western French city of Rouen since his death in 1199.

Despite the embalming ingredients, the heart turned to powder long ago, doubtless because the lead box cradling it wasn’t airtight. It’s so unsightly now that it’s kept from public view....