e-conservation the online Magazine 16, oct 2010.pdf

IDENTIFICATION OF IVORY BOOK COVERS
Introduction
Identification of Ivory
The cover material of four small books (Figure 1)
was the subject of a research project at Library
and Archives Canada (LAC). Three of the books
appeared to be produced of ivory or an ivory substitute,
and the fourth resembled tortoiseshell or
horn. Information was gathered on the history
and characteristics of ivory and ivory substitutes,
while identification tests were administered to
determine the exact compositions of the book
covers.
Extensive research revealed that there is very
little mention of ivory book covers in literature.
Though these ivory book covers are quite rare,
there are currently over 130 portrait miniatures
in the LAC collection. Since the history of ivory
use, ivory processing, and risks of deterioration
are very similar between ivory book covers and
ivory portrait miniatures, similar conservation
recommendations are proposed for use on ivory
book covers.
There are many methods of testing for ivory, yet
there is no test that is reliable, simple, and inexpensive
[1]. In fact, reliability is limited because
most tests can only prove that a substance is not
ivory, and cannot avoid a destructive aspect in
order to provide this diagnosis [1].
Testing methods
Preliminary examination revealed certain morphological
characteristics that aided in material
identification. For example, the size of the covers
indicated that they could not be composed of
smaller proteinaceous materials such as antler
or horn [2]. Photography under various lighting
conditions also revealed important details, such
as ivory grain patterns under transmitted light.
Lamellae grain patterns are present in longitudinal
cuts in ivory tusks, whereas Lines of Shreger
are present in cross-sections which provide distinction
from mammoth ivory [1].
Figure 1. For referral purposes, from left to right: Book 3, Book 1, Book 2, and Book 4.
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