Ethiopian books 'n' such

I'm coming to the end of my 3 week 'sabbatical' which included auditing a class irrelevant to my career and volunteering in the library where I had my start. I've been doing minor mending in their special collections. As it is a theological library, this means lots of bibles and other religious texts with of interesting and ornate bindings.

Two treasures of a particular bible collection are the two Ethiopian volumes. One contains the Gospels (on the left) and one the Psalms (on the right).

I've posted more pictures of these on my flickr account. Neither I, nor the owning library know much about these volumes apart from where they allegedly originated and their alleged contents. I would appreciate it if anyone has any insight or ideas for useful information to help better understand these volumes and some sense of their age.

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I emailed the illustrious Gary Frost about these volumes and he replied with some helpful insights, which I quote:

Yes, these are two authentic Ethiopian books and very magnificent examples. They have had a long service life, but modern repairs are evident only in board restitching. Both books are sewn on two paired stations with chains of stitch loops passing to each of the previous gatherings.

The first book features a complete Mahdar or case that appears to have the panel of another tooled binding applied to it. This book has a magnificent traditional blind tooling pattern featuring the array of multiple lines, annuals and rope chain tools. The goat leather is exceptional in color, grain and condition. The underlying cover boards are very elegant. The board opening shown includes a wonderful traditional doublure of pattern trade fabric. The endband leather braids appear lost, but the secondary tiedowns passing through the endcaps applear evident. The second book may have lost the spine covering or may be an example of a type with covered boards, but exposed text back.

The illumination and calligraphy are excellent and these are both exceptional productions of the traditional book crafts. Most of the examples brought to collections in this country are rather recent productions. Although they appear ancient, they are likely products of the 20th century. But I have no ability to estimate the age and the appearance of books much older are about the same. The illuminations would be key to dating as well as any internal evidence of ownership.