The title page identifies this manuscript as a copy of Kitab khawas al-jawāhir (The book on the properties of precious gems), written by Yaqūb ibn Ishāq al-Kindī in the ninth century. The work has 25 chapters, which are titled “On the knowledge of gems in general,” “On knowledge of rubies,” “On knowledge of emeralds,” “On knowledge of lapis,” and so forth. Each of these chapters gives basic information about these precious stones and their properties, as understood at the time. Information on the pricing of gems and the location of mines adds to the appeal of the work. The manuscript also contains a separate work on minerals by al-Kindi entitled Kitāb fi al-ahjār (The book on stones).