Archaeology Underwater: The NAS Guide to Principles and Practice

156 ARCHAEOLOGICALCONSERVATION ANDFIRST-AID FORFINDS

retained in situ. Fine nylon netting, polyethylene sheet-
ing or secured polyethylene bags can be used to cover ves-
sel tops to help prevent the loss of contents from ancient
storage containers. Removal of contents may lead to:

• collapse, due to lack of internal support;


• dilution, contamination and possible loss of contents,
  prior to analysis;


• poorer conditions for detailed examination and ex-
  cavation in controlled conditions (content samples
  should normally be passed on to environmental
  specialists as soon as possible).

The use of air-lifting is likely for potentially heavy
loads and all such lifts should be discussed and planned
in advance with all team members. All such large finds
should be immersed immediately in suitable containers,
ideally containing water from their immediate environ-
ment. Storage containers of the correct size should be
located on the dive platform, boat or barge, prior to lift-
ing. The contents of ancient storage containers, in par-
ticular, may start to deteriorate in ordinary conditions,
to the extent that the reliability of analytical results may
become seriously questionable: such vessels should be
sent as soon as possible following recovery to a conser-
vator who will be able to remove the contents and send
them for analysis while stabilizing the original vessel.

Fragile objects: The handling of waterlogged organics,
including very fragile small finds, such as rope, textiles,
bone or ivory, should be kept to a minimum. They
should be recovered on rigid supports wherever possible,
ideally incorporating some of the original context or
sediment, using either encapsulation in self-seal polythene
bags, or wrapping in thin polythene sheeting followed by
gentle bandage strapping.
The packing of material for transportation should aim to:

• maintain a waterlogged environment and mini-
  mize the risk of drying, particularly where finds are
  not due to be unpacked for several days;


• incorporate packing materials as cushioning to
  protect against vibration;


• minimize the risk of undue pressure on objects or
  abrasion to surfaces;


• keep the amounts of water used to a minimum (to
  prevent objects from ‘sloshing about’ and to reduce
  overall weight);


• render objects visible (to minimize the necessity for
  unpacking and handling);


• exclude air wherever possible;


• incorporate clear permanent labelling with full details
  of senders and recipients and additional labelling such
  as ‘fragile’ or ‘this way up’, as necessary;
  
  
  • pack samples according to the instructions of ana-
    lytical specialists (plate 16.4).
  
  
  
  

Note that large waterlogged finds, even if well-wrapped

in plastic, are likely to dry out even over a few weeks. This

method should therefore be used only for transport, with

finds being returned to wet storage immediately afterwards.

Approaches to Packing and Storage

• The availability of water (and electricity) supplies
  should be checked well in advance of a project,
  including access, local daily or weekly restrictions and
  water-table height (which may affect the use of
  water stills and de-ionizers).


• All finds should be stored separately, according to
  the materials of which they are made. In particular,
  metals of different types should never be stored toge-
  ther in solution due to the risk of galvanic corrosion.


• Gloves should be worn when handling objects:
  vinyl, latex or nitrile (non-powdered versions are
  available, which are often useful for those with sen-
  sitive skin).


• All packing and storage materials should be made
  of conservation-grade inert materials and should be
  sourced through conservation suppliers wherever
  possible. They may include: lidded polyethylene
  (polythene) buckets, boxes and bins; self-seal poly-
  thene bags, bubble-wrap; Plastazote (expanded
  polythene foam, which floats in water) polyether
  foam (which sinks in water) and bandages (to help
  provide support for large fragile objects).


• Basic recording materials, such as pens, labels, ties,
  scissors, tools etc. should be available to all staff
  responsible for finds handling.


• Small finds can often be stored waterlogged in self-
  seal bags (double-bagged) within polyethylene
  containers prior to conservation.


• Large-scale plastic bags can be made up from
  conservation-grade plastic sheeting to the appro-
  priate size, using a heat-sealer (budgets permitting)
  which melts the plastic and creates a welded seal.


• Non-bagged material should be stored in lidded, air-
  tight polyethene boxes, filled to the top with water
  to exclude air and cushioned using, for example,
  polyether foam, bubble-wrap or Plastazote, to help
  to reduce the risk of abrasion against container
  lids, sides and bases. Delicate objects may require
  custom-made envelopes of bubble-wrap and an
  added layer of thin foam.


• Sections of plastic drainpipes, suitably cushioned, may
  be useful for providing support for long, thin deli-
  cate artefacts, such as pieces of wood or rope.