Only one document was known from the royal chancellery of Leonor Plantagenet, queen consort of Castile; a charter issued in April 1179 and now preserved at in the archive of the Toledo Cathedral. But it was also known the existence of another charter dated in November ot that same year; a document originally kept in the medieval archives of the Hospital del Rey in Burgos and lost. The owner of such parchment has informed of its existence to the authors of this study, who offer here a historical, palaeographical and diplomatic analysis and a full transcription of the Latin text hitherto unknown. This discovery comes to confirm how original it was for the Spanish kingdoms in the Middle Ages the creation of royal house and chamber for a queen consort, and the availability and autonomous use of enough resources for the wife of Alfonso VIII.