They included detached leaves and single documents as well as illuminated manuscript books.
Law enforcement agencies, libraries and booksellers around the world were notified immediately. The matter has been reported in professional journals. The method and time of theft have not been determined, and none of the materials has been recovered.
An exact value has not yet been placed on them, but they are believed to be worth $350,000 or more. They are insured.
In a statement, Columbia said it has careful security procedures in place in the Rare Book Library and continues to review them.
The investigation is continuing, and it is hoped that the materials will be found and returned to the collection.