Isabel II was queen regnant of Spain from 1833 until 1868, when she was forced out by a somewhat muddled coalition of Spanish liberals and republicans. Her reactionary reign was a long series of palace intrigues, military conspiracies, and church meddling.
During the 19th century, there was a fashion for European sovereigns to commission small easily wearable coronet-style crowns (a fashion which was greatly promoted by Queen Victoria, the foremost monarch of the day). Queen Isabel commissioned this beautiful little yellow crown of diamonds, gold, and topazes. When she was forced out by the “Glorious” (but ineffective) revolution she took the crown into exile with her in Paris, however she willed it to the Atocha Chapel. If my sources are to be believed (and they are internet sources…so maybe they shouldn’t be) the little coronet is still used to adorn the church’s votive statue on high feast days.