Non-collection objects, such as facsimiles, reproductions and duplicate artifacts, are used to protect vulnerable items from the rigors of long-term display.
How to use non-collection objects as an effective conservation strategy for vulnerable objects
- • Replicas and reproductions: Rather than exhibiting fragile or highly valuable collection objects, the exhibit team can exhibit replicas or reproductions in their stead.
- • Undocumented or duplicate objects: The exhibit team can also substitute undocumented or duplicate objects (objects that are from the same time period but are not part of the museum collection) for original objects. The advantage of using such duplicate objects instead of creating a reproduction of the original is that it spares the collection object any possible damage from reproduction techniques. However, these objects are often identical to the original, and require careful documentation to prevent confusion. It is advisable to permanently mark these objects as exhibition materials, exhibit props or non-collection objects.
In what situations is use of a non-collection item recommended?
- • The physical circumstances of the exhibit are inappropriate for display of selected objects. For example, to remain true to a historic room’s original furnishings it might be necessary to hang a buffalo hide against a wall. Such vertical display would stress the original hide and a replica should be substituted.
- • The exhibit environment is inappropriate for display of selected objects. It may not be possible to modify the exhibit environment to create adequate environmental conditions or provide sufficient security.
- • A collection object is too vulnerable (or rare) to be put on display.
- • An object is in too unstable a condition to go on display.
- • Object rotation cannot be utilized as a conservation measure. Non-collection objects—reproductions, replicas, and duplicate artifacts—can be used when there is no replacement object in the collection for an object that must be rotated off display. Using non-collection objects can also be a useful strategy for museums that do not have the staff or resources to allow for object rotation.
- • The object will be used as part of a demonstration or hands-on program. Whenever possible, non-collection items should be used for hands-on programs and demonstrations that show how original objects, such as a piece of machinery or a musical instrument, functioned. Using the original object will accelerate deterioration.
Guidelines for using non-collection objects
- • Choose reproductions made from stable materials. Reproductions should be made of chemically stable materials that do not emit substances that could harm other objects. For example, plastic reproductions could emit volatile organic compounds. And reproductions should not contain dyes or pigments that could be transferred to nearby objects. This is especially important if the reproduction touches an object, or is placed with collection objects in a confined space where harmful vapors could build up.
- • Mark objects as replicas or reproductions. Replicas or reproductions are sometimes created using the same materials and techniques as the original piece; they may even be produced by the same manufacturers. To avoid future confusion, permanently mark a reproduction or replica with the current date (i.e. “Made in 2009”).
- • Label objects when displayed as replicas or reproductions. Artificial aging or distressing can make new items look aged. Curatorial intent determines whether or not these techniques are appropriate. In general, artificially aged objects should always be identified for the viewing public. Label copy can include the “preservation reason” behind using a reproduction; for example:
- "This reproduction object has been used because the original (seen in the photograph) is too fragile to be placed on long-term exhibit.”
- Labels that clearly identify an object as a replica or reproduction allow the public to evaluate that object as a non-collection piece.
How to minimize the risk of damage to original objects during reproduction
- Many museums buy reproductions available on the commercial market. Sometimes, however, copies are created specifically for the exhibition.
- Creating copies of an object from the collection can expose that object to a great deal of risk; objects have been damaged during the mold-making process and by rough handling. The following precautions should be taken:
- • Have a conservator examine the objects before beginning any replication processes to insure that they can withstand handling. If the object is fragile or could be damaged by the reproduction process to be used, select another object for reproduction or use a commercially available reproduction.
- • Have a conservator review all methods and materials to be used in reproduction to ensure they are safe for the collection object. For example, making a mold directly from the object’s surface could damage the original material irreversibly if the mold should shrink around the object or contaminate the object’s surface.
- • The scope of work or reproduction contract should include the unacceptability of object damage. The person undertaking the reproduction process must understand the need for care when handling museum objects, should be familiar with object handling requirements, and must be willing to take direction from museum staff.
• Restrict the object from leaving the museum premises, whenever possible. (See Guideline 4.3)
Guidelines for making two-dimensional Reproductions
- Two-dimensional objects are more easily reproduced than three-dimensional objects, which are often more costly to replicate. The following precautions should be taken when making two-dimensional reproductions:
- • Using digital scanning or a color copier. This is the least expensive method for reproducing two-dimensional, paper-based objects:
- • Trained museum staff should handle the objects.
- • Limit the number of times that the original is exposed to the light of the scanner or copy machine.
- • The object must fit onto the glass imaging plate of the machine without being folded, bent, creased or otherwise damaged.
- • Use special machines that support the binding when copying books.
- • Good photographic reproductions. These can be made from a 4x5 inch transparency of the document.
- • Such a large transparency may require a professional photographer.
- • If film is used, Ifachrome (also called Cibachrome) is the most chemically stable process for color images. Use polyester base paper
- • Photographs can also be printed on papers that imitate the original material.
- • See Guideline 3.5 for precautions to follow when photographing objects.
Guidelines for making three-dimensional reproductions
- There are several methods available to reproduce a three-dimensional object:
- • Individually crafted reproductions based on exact measurements. In some cases, the reproduction uses original materials and techniques. When exact reproduction is less important, other materials that are easier or cheaper to work with may be used. However the material must be stable and non-hazardous to other original objects that might be on display nearby.
- • Casting a replica from a mold taken from the original is perhaps the most common technique, especially for intricate objects or when multiple copies are to be made. However, the multi-step process of taking a mold of the original object can be damaging. To prevent damage, employ a professional cast-maker or museum specialist and insist that they follow guidelines outlined by a conservator. It is especially important that the mold material does not shrink around the object, and that an appropriate isolating layer be used to ensure that the original is not contaminated.
- • Faux finishes, wood laminates and photographic inserts are inexpensive methods of reproducing many finishes. These finishes imitate the original from visitor viewing-distance, but are easily identified upon close inspection. These finishes may require special cleaning techniques.