The Cave of Treasures presents itself as an extended prequel to the New Testament account of the gifts of the magi. It was composed, apparently, in Syriac. It survives also in various derivative translations.
We published a translation of it by Alexander Toepel in Old Testament Pseudepigrapha: More Noncanonical Scriptures, volume 1 (ed. Bauckham, Davila, and Panayotov; Eerdmans, 2013), pp. 531-84. But one could also make a case for including it among the New Testament Apocrypha.
I have collected links on the Cave of Treasures, including to an old German edition and an old English translation here, with more here, here, and here.
Cross-file under Old Testament Pseudepigrapha Watch, More Old Testament Pseudepigrapha, Christian Apocrypha Watch, New Testament Apocrypha Watch, Syriac Watch, and 'Tis the Season.
UPDATE: Please pardon the glitched links above. I have unglitched them!
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