From J. M. Cronyn's "The Elements of Archaeological Conservation" (1990),
Routledge, New York, pages 263 - 275

- there is a difference between what to do with dry leather and wet leather
- Cronyn recommends taking dimensions from leather while wet, since upon
shrinking, details such as stiching and eyelets can be obscured. A photo
shows dimensions being taken by tracing around the artifact with a
waterproof marker onto a sheet of Mylar

Passive stabilization, to hold for conservation, etc.:
Dry leathers: "As with all moisture-containing amterials, the relative
humidity (RH) has to be controlled to allow skin products to retain the
optimum quantity of water but to prevent the growth of micro-oranisms. For
leather this is in the range of 50-60%, for parchment 55-60%; where the
artifact is painted or gilded it is especially important that the RH does
not fluctuate. If products come from an extremely dry RH, then they are
dampened only gradually. Temperatures less than 18C are advised, and much
reduced temperatures discourage biological activity; this is often put to
use with furs to prevent decay of the hair roots and loss of hair. Control
of light levels (150 lux or 50 lux for dyes, manuscripts and furs) and
elimination of UV and sulphur dioxide prevent further deterioration,
whilst insect damage is prevented by good housekeeping." (p272)

Wet Leathers: "Loss of water must be prevented; this is done simply by
storage in sealed containers where growth of micro-organisms is
discouraged by refridgeration. Again, deep freezing has been suggested and
in fact seems to do no damage. Excessive leaching of tannins in storage
solutions is avoided by use of a small quantity of water rather than by
immersion." (p. 272)

I recommend this book highly for all archaeologists. There are some simple
techniques you can apply in the field and in the lab to best preserve your
artifacts. It includes a discussion of agents of deterioration and
preservation, archaeological environments, general techniques of
conservation, siliceous and related materials (stone, glass, cements and
composites, ceramics), metals (iron, lead, tin, copper, silver, gold and
their alloys), organics (wood, skin and gut products, bone, horn,
tortoiseshell, feathers, textiles, and organic minerals -- jet, amber).

--Megan Springate.

> Hi,
>
> As you all know, lots of leather is recovered from nineteenth and
> earlyt twentieth century sites e.g., shoe leather, harness, etc.  OK,
> generally speaking, if its just fragments or scraps, I have just  put
> it in paper bags and let it dry for later processing or curation.
> However, let's say I recover a leather or cloth artifact that  seems
> worthy of more extensive long-term storage, curation, restoration or
> whatever.  What are reocmmendations for short to medium-term storage
> of something like a damp or waterlogged shoe.  Sealed container?
> Refrigeration? Freezing?  Thinking about coming out of the field,
> stabilizing, and holding for further work ...  Comments or
> suggestions.   Thanks in advance.
>
> --
>
>
> Mark C. Branstner
>
> Illinois Transportation
> Archaeological Research Program
> 209 Nuclear Physics Lab, MC-571
> 23 East Stadium Drive
> Champaign, IL 61820
>
> Phone: 217.244.0892
> Fax: 217.244.7458
> Cell: 517.927.4556
> [log in to unmask]
>