A Canonical Coronation (Latin: Coronatio Canonica) is a pious institutional act of the Pope, duly expressed through a Papal Bull in which a Papal Legate or a Papal Nuncio designates a crown, tiara or stellar halo towards a Marian, Josephian or Christological image under a specific devotional title that is being venerated in a particular diocese or locality.
Previously, the authorization was issued directly from the Holy Office through a dicastery called the Vatican Chapter, later designated to the Sacred Congregation of Rites. Since 1989, the act has been carried out through the authorised decree by the Congregation for Divine Worship and the Discipline of the Sacraments.
Canonical coronation Wikipedia
The earliest custom of crowning images dates back to the Order of Friars Minor Capuchin who through their evangelical missionaries, collected massive amounts of jewelry in exchange for indulgences which would then fund the golden crowns or accessories of the Blessed Virgin Mary. A considerable advocate for this practice was the Capuchin Girolamo Paolucci di Forli (born 1552 - died 1620), known during his lifetime as the self-proclaimed "Apostle of the Blessed Lady".
In addition, the Marquis of Piacenza and Count of Borgonovo, Alessandro Sforza Cesarini died, leaving in his will and testament dated on 3 July 1636, requesting a provision in which a large sum of money was to be invested to fund crowns of precious metals for the coronation of the most celebrated Marian images in the world.
The practice and public declaration of coronation became widely popular in the Papal states prior to the 19th century as growing to approximately 300 coronation rites. On 29 March 1897, an official rite was included in the edition of the Roman Pontifical which granted plenary indulgence for the faithful who participate in such acts.The very first Marian image crowned without a direct Papal approval was by Cardinal Pietro Sforza Pallavicino with La Madonna della Oropa on 30 August 1620.
The first Marian Pontifically crowned was the painted image of La Madonna della Febbre (Madonna of Fever) on 27 May 1631 by Pope Urban VIII through the Vatican Chapter located at the sacristy of Saint Peter's Basilica.
The solemn prescription of ritual to crowning images is embedded in "Ordo Coronandi Imaginem Beatae Mariae Virginis" published by the Holy Office on 25 May 1981. Prior to 1989, papal bulls concerning the authorization of Canonical Coronations were handwritten on parchment. After 1989, the Congregation for Divine Worship and the Discipline of the Sacraments began issuing the specific recognition to crown a religious image, spelling out its approved devotional title and authorizing Papal legate.