Avoid attempting to clean objects in the field by extensive scraping, brushing, rubbing, or washing. This can cause damage to the surface edges of the object. Wait to clean objects under proper laboratory conditions.
Surface soil and dirt must be removed from an object before a label is applied. Dry cleaning methods are recommended for all objects. Excessive cleaning beyond the point necessary for analysis or conservation is discouraged.
The use of water to clean metals, dry wood, and fragile or delicate bone is especially damaging. Even sturdy bone can warp, split, or crack as a result of changes in moisture content. Washing of all objects including those of stone may remove mineral and organic residues providing evidence of past tool use of container contents.
Consult a professional conservator before attempting to clean skin or hide products, feathers, basketry, cordage, etc., or if you are unsure of how to clean an object.
Any archaeological material requiring special treatment, such as those which must not be cleaned, must be separated from the rest of the collection and labeled clearly with the special treatment required. Items not cleaned in anticipation of their utility in future analyses should be documented with a description of the proposed analysis and a report on how the item was handled in the field and laboratory prior to being packaged for curation.
Label Application and Materials
All materials accepted for curation must be identified with a site number designation and catalogue number. The site number should be the primary portion of the label, as, for example, site 10CA483, with the catalogue number place below the site number to minimize confusion between the numbers. Additional annotations may be appropriate, such as the "project year" for materials recovered from a site that was previously collected.
It is desirable to have the label permanent yet reversible in the event that temporary removal for photographing or analysis is necessary. Sandwiching an ink label between two layers of reversible resin varnish is the suggested method. When labeling an object, use a water-based ink, preferably India ink on light colored items and white ink on very dark-colored items. When a non-waterproof ink, such as Higgins white ink is used, it must be covered with a sealing coat of varnish. Never use "White-Out" or "Liquid Paper" for a label base, as they chip, peel, and are difficult to remove. If a white or colored background is necessary, use reversible colored lacquer or an acrylic polymer emulsion on top of the removable lacquer base. Acrylic artist's colors dry quickly and remain flexible, but are difficult to remove if painted directly on some materials as the base coat. Labels on tags, bags, or vials should be made only with permanent or indelible ink.
Whenever possible, labels should be applied to the archaeological object as described above. Should the character of the object be such that direct application of a label is inappropriate (all perishable items, for example), an acid-free string tag or cotton tape tag label may be secured to the artifacts or its container.
Labels must be clearly legible and applied securely in the least conspicuous place so as not to detract from the photographic or analytical values. Care should be taken to place labels in areas least likely to be subjected to handling or other abrasion. Very small artifacts, such as beads, need not to be labeled directly, but should be placed in clearly labeled bags or plastic vials.
For a discussion of methods for labeling objects of various material types, see Museum Registration Methods, 3rd edition, revised, pages 52-63, American Association of Museums, Washington D.C.