Altered Book enthusiasts will enjoy these images (as well as those who
admire Medieval Art). This is a current exhibit at Getty.
Shrine and Shroud: Textiles in Illuminated Manuscripts:
http://www.getty.edu/art/exhibitions/shrine_shroud/
This gives you some historical reference for including some fabric
"treasures" in your altered books.
YES - students of ALL faiths can admired these images. Illuminated
Manuscripts is an ideal place to start when you are discussing the
book as art. These books had highly embellished covers and often
shrine boxes to hold them. Art about religion definitely has its place
in the art curriculum. I know there are many out there who will
disagree with me - I don't want to start a debate on this topic (you
can send your replies to me off list).