A tiara may be placed on a quinceañera’s head during the ceremony.
The crowning symbolizes the celebrant’s special status and the transition being recognized. In some families, a parent, godparent, or another honored person presents or places the tiara during the religious service or reception.
The custom is related to the quinceañera’s formal presentation, but it is not universal. Some celebrations use a crown, comb, jeweled headpiece, or no special headwear. A tiara is therefore the canonical name for the familiar jeweled crown-like accessory, not a required part of every event.
The tiara can also coordinate with the dress and jewelry. Its decorative role is separate from religious objects such as a Bible or rosary.