English: Miniature (capital S) from a manuscript of the Roman de la poire. This is the earliest known visual depiction of a lover handing his heart to his mistress. The heart is in the shape of a pine-cone (point upward), in accord with anatomical descriptions of the human heart at the time.

Caption by BNF: Atelier du Maître de Bari. La dame de Thibaud et Doux Regard.[1][2]

See Vinken, P (2001), "How the heart was held in medieval art", The Lancet 358 (9299): 2155–2157[3]:

"The first illustration of a heart outside the anatomical literature occurred as late as the 13th century, in a French manuscript, written by an unknown poet and entitled Roman de la poire (Romance of the pear). This story takes its title from a scene in which the damsel offers a pear, analogous to Eve's apple, to her sweetheart. In the tale, the suitor's gaze is represented as an actual character called Douz Regart (Sweet Looks). In a miniature, within the calligraphic curve of a golden capital S, he is pictured kneeling before a lady and offering her the lover's heart. The shape of this heart resembles the form of a pine cone–a shape that accords with descriptions of the heart in anatomical literature since Galen and Avicenna."

Vinken cites the source of the image as "FR, MS. 2086, plate 12. National Library, Paris, France".

The immediate source of this image, a webpage at univ-montp3.fr, misreports the source as MS fr 1584 (but giving the correct folio, 41v), dated c. 1275. Vinken also misreports the ms signature, giving 2086 instead of 2186 (presumably an unnoted typo).