Conservation and restoration of bone, horn, and antler objects

Skeletal bone is usually smooth except for areas of attachment to muscles, tendons, and ligaments, while antler generally has raised bumps and protrusions across the surface.

Similarly to bone, antler may be used in its natural form, polished with abrasives for a glossy surface, and treated with a burning process for a charred finish and color.

Antler has been used for numerous objects throughout history including tools such as hammer batons, knife handles, pressure flakers, and conical arrow points.

[4] Examples of ivory objects include: horns, handles and inlays for ceremonial weaponry, jewelry, and decorative arts; statuettes, regalia masks, and even triptychs.

The most common physical forces on bone, antler, and horn are mishandling, over handling, being dropped, or being unbalanced while on display or in storage causing stress compression on weak spots.

Temperature that is too high, too low, or fluctuates in a large range causes materials to become brittle, fragile, or deteriorate through chemical methods such as acid hydrolysis.

Pollutants include gases, aerosols, car exhaust, emissions from nearby factories or construction work, even the off-gassing of volatile organic compounds from other museum objects.

[13] A filtered air-conditioned storage area can control the temperature and relative humidity while simultaneously circulating the air which removes pollutants and prevents mold growth[14] while creating an uninviting environment for pests.

A relative humidity level that is too low (dry, below 30%) with cause the bone, antler, or horn to crack; too high (damp, over 75%) and they are subject to expansion and mold growth that can disintegrate or discolor.

This ranges from physically misplacing an item, improper storage or display, and lack of cleaning the object and surrounding area that increase the likelihood of the above-mentioned agents of deterioration.

Items that contain bone, antler, or horn should always be lifted and moved in a manner that is fully supportive and does not place unnecessary stress on weak areas or attachment points; using an acid-free tray is highly recommended.

[2] Bone, antler, and horn objects are stored in tightly closed display cases or drawers to buffer them from sudden changes in temperature and relative humidity while shielding them from dust and dirt.

[17] Proper storage also aids in the regulation of temperature, relative humidity, and safe illumination levels, which can have disastrous effects on these organic materials if they fluctuate.

As an added safety measure you can also implement a policy to minimize the opening of doors and windows, as well as retrofitting seals and doing secondary glazing on glass.

[18] Finally, pollutant absorbers, such as activated charcoal can be added to display cases, or even placed in storage areas to add another layer of protection.

Bone, antler, horn, and ivory are not particularly susceptible to insect damage, such as termites or booklice, so long as the objects were properly prepared before being added to the collections.

[17] It is recommended that you create a pest management plan that takes all of the following into consideration and work with pest management professionals to ensure the continued safety of your collections, these can include but are not limited to: Preventive care can protect bone, antler, horn, and ivory objects from damaging elements, but objects on display are put at risk and therefore need to be carefully prepared as well as monitored.

The adoption of protective enclosures such as exhibit cases with appropriate temperature control can aid in "Minimizing relative humidity fluctuation, as well as reducing handling, soil accumulation and infestation of microorganisms, insects, and rodents.

Bone, antler, horn, and ivory objects can be fastened to the mounts through the application of wires or flat acrylic plastic clips.

[5] Rotating the bone, antler, horn, and ivory items on display, following a set timeline, prevents them from being exposed for extended periods, thus reducing the risk of extensive light damage.

Conservation science is a varied and complex field with aspects devoted to the study of objects’ materials, uses and origins, how they degrade over time, and techniques for care, storage, and display.

Antler, bone, and horn have been heavily used for tools and other objects for at least 1.5 million years, and continue to be used today, though modern materials such as plastic and metal are now predominant.

As bone, antler and horn are all derived from living organisms, determining the level of carbon-14 versus carbon-12 is considered quite effective and is the most widely used form of absolute dating.

Bone, horn, and antler objects are often part of museum collections and are unique because they require special considerations in terms of care.

Air-drying is the simplest method but must be conducted carefully and monitored well, as bone, horn, antler, and ivory objects are each susceptible to fluctuations in temperature and humidity and liable to crack.

After drying out the intended specimen simply create a "bug box", this can be any container large enough to house both the bones being cleaned and the dermestids doing the job.

"[32] In 2016, conservators from the National Museum of Ireland assisted the University College Dublin Library in a conservation-restoration effort after a mishap that caused damage to the deer skull, antlers, and other skeletal elements.

Microballoon spheres and Paraloid B72 were used as gap filler and in the structural remodeling due to their high bulking ability while reducing the contact surface area (and further damage) to the bones, long-term stability, and easy removal.

Using the same technique throughout the restoration "limit[s] the number of different substances introduced to the specimen and enable[s] treatment to be identified as a single phase of conservation in the future.

Copper plated mild steel welding rods, riflers, files, and wood carving chisels were used to shape skeletal element remodels, then painted using an in-paint containing earth pigments in a Paraloid B72, IMS, and acetone solution.