There are many different styles of depicting the annunciation across different art movements, with this one being fairly similar to the Late Gothic movement. Gabriel comes in from above, drawing God into the composition. The panel is sized at 52cm by 45cm, making them slightly smaller than the panels created in the artist's next series of doors, nicknamed the Gates of Paradise.
Gabriel releases the dove of the Holy Spirit, another symbolic moment in this trimmed down scene where only the most significant figures were included. Perhaps the artist felt that these panels were too small to include any more detail. Gilded bronze was used to complete this finish though it is likely that other mediums were used in preparation for the final piece, such as charcoal for study drawings.
The north doors took on considerable impact from local pollution before finally being taken indoors in order to preserve them for future centuries. Much of the gilded elements has worn away now but there is still plenty in tact to allow us to understand the beauty of Ghiberti's first major project.
There are many famous depictions of the Annunciation besides the panel produced here, with perhaps the most notable being Annunciation by Leonardo da Vinci, The Annunciation by El Greco and Annunciation by Jan van Eyck (one of several by this artist). Christian themes such as this were particularly common during the Renaissance and Baroque periods in European art.