In early February we wrapped up inventorying and rehousing collections that originated in Missouri. The work was followed by two weeks of cleaning, and as a result we’ve completed one of the regions held in the collection. So you may be wondering what we were cleaning. During the inventory, we encountered bone and antler objects covered with salt crystals and patchy dormant mold. The objects were cleaned before they were stored inside their new boxes to remove salt and minimize the risk of mold spreading to unaffected objects.
Where did the mold and salt come from and why are they a problem?
Mold spores are found everywhere in the environment. When the humidity is high, those spores germinate resulting in mold. Because it is a living organism, mold is classified in the museum world as an agent of biological deterioration. It eats organic matter, in this case the dust resting on the outer surface of bone or the bone itself, and secretes waste that can stain or damage the surface that it is growing on. Mold can appear to be dormant, but when the conditions are right mold will generate spores that are easily borne on the wind, allowing it to spread quickly.
Salts on the other hand are considered chemical agents of deterioration. They are brought into museum collections on the objects themselves. Dissolved salts present in groundwater can be absorbed by porous objects, such as bone, while they are buried underground. After the water evaporates the salts are left behind. Excessively humid conditions can dissolve soluble salts, allowing them to move through porous objects. When they arrive at the surface they form crystals. If the crystals form below the surface they can exert enough force to cause damaging cracks and spalling.
Mold and salt thrive in damp environments where the Relative Humidity (RH) is above 65%. The institute’s storage area is located in the basement, which does not have a controlled climate, so mold and salt are an unfortunate reality. Currently, the RH in the basement is somewhere below 15% (15% is as low as our monitoring equipment can read). RH levels this low shouldn’t support active mold and salt growth, so what we found is inactive, but it is hard to say when and for how long the growth of mold and salt was last active.
At the Peabody we are committed to maintaining the longevity of this very important research collection and salt and mold pose a risk to its scientific viability. Damage to the surface of artifacts caused by mold and salt can negatively impact the research value of the collection.
How do we prevent mold and salt?
While we don’t have an HVAC system maintaining the environment in basement storage, we have adopted a few practices that will mitigate and prevent future growth of mold and salt. First, we use dehumidifiers during times of high humidity that typically arise during the summer. Second, we are moving the artifacts currently stored in open drawers and rehousing them in closed archival boxes. The enclosed space of a box helps create a buffer that protects the contents from rapid shifts in RH that lead to mold and salt growth. The boxes will also keep future mold growth from spreading; something that was not possible with open-drawer storage.
In addition to the rehousing, we have implemented a cleaning program. When mold and salt are identified we isolate the effected object to keep spores from spreading. We clean the affected artifacts with a dry brush and vacuum. After we clean we use sachets of silica gel to absorb excess moisture, thereby providing another buffer against cycles of RH increases and decreases. In six months we’ll check on the status of the bone to see if the mold and salt are staying away.
My name is Emma Cook, I am the Administrative Assistant at the Robert S. Peabody Institute of Archaeology. I have a background in archaeology, history, and museum studies with undergraduate and graduate degrees from the University of Georgia and Tufts University. Aside from my administration duties, I work with the Peabody’s collections. Recently I’ve been involved in the Inventory and Rehousing Project and I am working with collections on the first floor South Alcove, located in one of our gallery/classroom spaces.
The Robert S. Peabody Institute of Archaeology collection comprises nearly 600,000 artifacts, photographs, and archives. Some of these materials are displayed and used for teaching, while many reside in our collection storage. What is unique about much of our collection space is its original storage. The bays and drawers in which many of these artifacts inhabit are almost as old as the Peabody itself, the bays being first built in the early 1920s. However, below the surface of these pine wood bays and drawers are a collection of uncatalogued objects that have hardly come to light (literally), with some still stored in the tin foil and paper bags they were placed in upon archaeological excavation many years ago.
The antiquated charm of these wooden bays is not enough to meet the need of accessible storage for our collections and the goal is to replace them with new custom-built shelves. In preparation of this storage renovation, objects need to be identified, catalogued, and rehoused. This work is completed through our Inventory and Rehousing Project.
I began my work simply inventorying the objects in each drawer of each bay in the alcove. Some of these objects were already identified, numbered, and recorded in Past Perfect – a museum software that is the standard for cataloguing museum collections. Through this software, the Peabody collection is documented and made accessible online. My job was to make sure these objects were accounted for and in the right place, as well as properly rehoused and organized within the drawers. Sounds pretty easy right? Well, eventually things changed as I came across several drawers and bays containing objects with old numbers or no numbers at all. This is where my cataloguing efforts began.
Cataloguing lithic materials from Puerto Rico, Cuba, and New England (Each sticky note marks an object without a number)
Lithic materials, primarily ground stone Celts from Puerto Rico
Cataloguing is the process of recording details about an object into a collection catalog or database that documents the information of each object as well as its location in storage. Through this process each object receives a unique number. This number is physically attached to the object and appears in records related to the object in Past Perfect. In museums and archives, objects or materials in a collection are normally catalogued in what is called a collection catalog. In the past, this was traditionally done using a card index, but in the present-day it is normally implemented using a computerized database – for the Peabody this is Past Perfect. Some of the objects I came across with “old numbers” were either connected to the Peabody’s past card index cataloguing system or the Peabody’s original numbering system (i.e. 1,2,3,…. 78,049).
Each object was given a new number associated with the Peabody’s present catalog numbering sequence (i.e. 2019.1.123). This numbering sequence is a three-part number, making it both simple and expandable. The first part of the sequence is the year in which the object was accessioned or catalogued (i.e. 2019). The second part of the sequence is given to objects in chronological order based on when they were first accessioned (i.e. 2019.1). The third part of the sequence gives a single object a number in chronological order (i.e. 2019.1.1). Objects that had an affixed label had the new number written on the label. Objects without labels had their numbers painted on with ink. A solution called B72 is applied to the object before the ink in order to protect the original surface of each object. This solution is not harmful to the object and can be easily removed if a mistake is made or the object needs a different number.
The cataloguing process is not an easy one, nor is inventorying and rehousing a collection. The process may be slow and tedious, but it does have its rewards. By using a great deal of care, time, and effort, rehoused and identified objects can be used for teaching and research. Not only can collection staff have full access to the collection, they can provide a safe and accessible place for these materials in storage. The cataloguing process may seem like a trivial task, but it just goes to show – it’s more than a number.
For more information and reading on the Inventory and Rehousing Project, see the following blogs below:
Adventures in Ancient China is one of the newest Learning in the World programs at Phillips Academy. During spring break 2019 eighteen students experienced some of China’s most dynamic history and archaeology, along with spicy cuisine, fantastic religious art, and new friends.
After exploring the impressive architecture of Ming and Qing dynasties at the Summer Palace, the Tian Tan, and the Forbidden City we engaged with some of Beijing’s Intangible Cultural Heritage. UNESCO defines intangible cultural heritage as “the practices, representations, expressions, as well as the knowledge and skills (including instruments, objects, artifacts, cultural spaces), that communities, groups and, in some cases, individuals recognize as part of their cultural heritage.” This can include oral tradition, performing arts, rituals and festivals, traditional knowledge, and craftsmanship.
Students participated in a workshop with a local artist who makes and decorates figurines of Lord Rabbit, also known as Tu’er Ye in Beijing. Tu’er Ye, once worshiped in the pantheon of local deities, was renown as a healer and maker of elixirs. The moon goddess Chang’e sent Tu’er Ye to use his/her knowledge of medicine to save the people of Beijing from a plaque. Tu’er Ye probably appeared as early as the Ming Dynasty, often as a clay figurine for inclusion in household shrines.
Tu’er Ye is a rabbit with a human body adorned with the outfit of an ancient general: helmet, scarf, shoulder-draped golden armor, broad belt and big boots, while holding an alchemist’s pestle and mortar. Tu’er Ye figures prominently in the Mid-Autumn festival and the figurines may have become toys to occupy children during festival preparations.
A handful of artists continue the tradition of making and decorating the figurines. Making the Tu’er Ye figurines is one of Beijing’s more than 12,000 intangible cultural heritage items. It was inscribed on the national list in 2014.
Adventures in Ancient China is generously supported by The Schmertzler Fund for Exploration and Experiential Education.