Conservation

The projects featured in this portfolio took place under the guidance of the Israel Antiquities Authority.

Working with Mosaics

Israel Antiquities Authority (IAA) Laboratory

These projects were completed as a laboratory technician for the Israel Antiquities Authority Fine Arts Conservation Department, housed in the historic Rockefeller Museum in Jerusalem, Israel.

The process of conserving mosaics that cannot remain in their original sites:

All things in conservation begin with documentation. The site will be measured, photographed, and sketched to provide references for archaeologists, conservationists, and historians. While the mosaic is still attached to the original site, it will have layers of adhesive and canvas applied to the top surface that will serve to secure the shape and form. Then it will be cut out of the mortar attaching it to the Earth and placed on an aluminum board with a honeycomb core. Temporary fills composed of sand and plaster will be placed on the larger lacunas and edges to protect it while it is in transit.

Once it arrives at the lab, the fills will be removed, along with the canvas and adhesives. The mosaic will be meticulously cleaned, and then begins the great puzzling feat of replacing missing tesserae. Sections with a small amount of tesserae missing (where the pattern is still obvious) will be replaced with loose tesserae found at the site. This is done both to conserve both the beauty and the foundation of the piece. The more compact the tesserae are, the less likely they are to become loose in the future and further erode the design. Lacunas that are missing too many tesserae to accurately understand the pattern will be replaced with mortar filling.

This entire process takes many months and teams of dedicated staff members with exacting eyes and endless patience.

Fish Mosaic from Lod (as seen from bottom)

This is a section of a mosaic from Lod, Israel dated to ca.300 CE. This is a view from the underside of the mosaic (where the tesserae would have sat in the mortar). Unfortunately, this is not the first repair this mosaic has been through. Past conservators removed it from its original mortar and placed it in a concrete mortar. The top of the mosaic is currently attached to a sheet of canvas via a water soluble adhesive. Once the concrete is removed, it will be replaced by a less abrasive and damaging mortar and attached to an aluminum board, allowing it to be moved without further damage.
Cleaning tesserae

Before the puzzle begins, the tesserae must be painstakingly cleaned. They are often covered in chunks of mortar, dirt, and cement.
Section of Nesher Ramlah Mosaic

Good as new!
Cleaning (Before)

The protective canvas that holds the mosaic in place during transportation is attached by an adhesive that can, unfortunately, leave a lot of gnarly residue. In order to remove the canvas, it is first covered in hot water and then carefully peeled off.
Comparison

The left side is clean, the middle still has canvas attached to it, and the right side has had the canvas removed, but still has a great deal of residue from the adhesive still left on it.
Cleaning (after)

Once the canvas is removed, the mosaic is scrubbed down with sponges and more hot water. Although the mosaic is pretty durable, if the mortar gets too wet it can loosen the tesserae, so it is important to do this quickly before the water sits for too long. Any excess residue not removed through sponging will have to be scraped away with scalpels.
Moving Mosaics

Moving a mosaic takes quite a team. When the mosaics are removed from their original site they are affixed to an Aluminum honeycomb board, which can be transported with (relative) ease.
Mosaic Section from Nesher Ramlah

This section of a "geometric book" mosaic from Nesher Ramlah has been carefully documented, removed from its original mortar setting and reattached to an aluminum honeycomb board. As this mosaic has strong recognizable geometric patterns and the original archeologists were able to bring in loose tesserae from the immediate surroundings, it is possible to "complete" some of the missing sections. Sections that have patterns no longer legible will be filled with a plain mortar.
IAA Mosaic Conservation Lab

View of mosaic lab from above
Removing mortars from Lod mosaic

The concrete mortar is carefully chiseled off. If a tesserae comes loose, it is immediately re-attached to the canvas with a water soluble glue.
Mosaic from Nesher Ramlah

Before transporting it, the blank sections were filled with a fine mortar to prevent the stones from shifting. The sections that will be replaced with tesserae must be cleared of this excess mortar.
Fish Mosaic from Lod (after cleaning)

Fish Mosaic from Lod (after cleaning), as seen from the underside.

Working on frescoes

Ghassulian Star Fresco (ca. 4000 BCE)

Gentle, light cleaning of detritus using cotton swabs and paraloid.
Ghassulian Star Fresco (ca. 4000 BCE)

Gentle, light cleaning of detritus using cotton swabs and paraloid.
Ghassulian Star Fresco (ca. 4000 BCE)

Gentle, light cleaning of detritus using cotton swabs and paraloid.

The Ghassulian Star Fresco is among the oldest known frescoes.

For more information, you can read a recent Times of Israel article about the Fresco's restoration HERE.

Working in the field

Ummayid Bath House

The edges of the mosaic are first cleared of debris, to allow the mortar to adhere directly to the mosaic tesserae.
Ummayid Bath House Conservation

Once the edges have been carefully cleaned of debris they are wet and touch of lime powder is sprinkled on. Then a layer of mortar is applied.
Ummayid Bath House Construction

Once the mortar is almost done drying it is patted down with a hard brush and covered in dirt. The dirt both camouflages the mortar and slows the drying time, a necessary precaution as the site lies under a hot July sun in the Middle East.
Mamshit

Significant holes (or lacunae) in the mosaics loosen all of the surrounding tesserae. If the original tesserae are available and found to match the design it is possible to replace them. However, this is not always possible, in which case the lacunae are filled with mortar to prevent further decay. In the picture above a large lacuna is visible. The edges of the lacuna are not sufficiently held in place and will cause the surrounding stones to loosen.
Ummayid Bath House

This Ummayid-era bath house was discovered in 2016 near Bet Shemesh, Israel during the construction of a new highway. The site still had intact mosaics. The conservation team came out to the site while archaeologists were still excavating, in order to place some protective mortar around the edges to prevent further erosion of the mosaics. Once the layers of dirt that had been covering and protecting it were removed, and the site was populated with large boot-wearing archaeologists damage was inevitable.
Mamshit (a.k.a. Memphis)

The archeological site and national park of Mamshit dates back to the Nabatean era. Thanks to the dry desert climate, this Byzantine-style church still has its original floor mosaics in place.
Yehi'am Fortress

The stones of the wall were removed and sorted into piles based on size.
Yehi'am Fortress Dry Stone Masonry

The national park that houses Yehi’am Fortress is responsible for maintaining the site. One of the dry stone walls leading up to the entrance had fallen into disrepair and posed a safety hazard to visitors.
Yehi'am Fortress

The stones were then replaced by carefully fitting them together and filling the center with hearting stones.
Yehi'am Fortress

The stones were then replaced by carefully fitting them together and filling the center with hearting stones.
Yehi'am Fortress

Passerby need no longer fear for their toes!
Caesaria Fortress

The ashlar that will be replaced must be chiselled out, piece by piece.
Caesaria Fortress

The space must be clear of not only the old ashlar but also the old mortar. This is vital to ensure the new mortar will adhere properly to the surrounding ashlars.
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Description
Caesaria Fortress

Occasionally the sandstone ashlars of the crusader rampart wall become so eroded (the result of continuous sea spray and wind beating against it) that it poses a serious safety concern to visitors. When this occurs the stones must be removed and replaced.
Caesaria Fortress

Occasionally the sandstone ashlars of the crusader rampart wall become so eroded (the result of continuous sea spray and wind beating against it) that it poses a serious safety concern to visitors. When this occurs the stones must be removed and replaced.
Caesaria Fortress

Occasionally the sandstone ashlars of the crusader rampart wall become so eroded (the result of continuous sea spray and wind beating against it) that it poses a serious safety concern to visitors. When this occurs the stones must be removed and replaced.
Mamshit

Once the area around the hole has been scraped clean, it is dampened and a layer of mortar is applied to it. The mortar must be evenly applied and the surrounding stones are carefully sponged down to prevent layers of lime from drying atop them and affecting their color.
Mamshit

Sponging down entire mosaics while tedious on the knees, is a rewarding experience. When the tiles are wet their colors practically glow. Since the mosaic is uncovered and located in the middle of the Negev desert it is rare to see it at its peak -- radiant, vivacious, and dust-free.
Mamshit

ccasionally, if a large section feels loose, mortar can be applied to fill in the gaps. This is done by covering the entire surface in a very thin layer of mortar. The mortar will fall into the cracks, dry, and strengthen the overall mosaic. The excess must be immediately sponged off before it can dry.
Egyptian Mudbrick Palace of Beit She'an

The fortification layers atop the original mud bricks have begun to decay. This decay is likely caused by a combination of weathering and site visitors who are eager to climb the walls for a better view of the valley.
Egyptian Mudbrick Palace of Beit She'an

The mortar and debris surrounding the brick must be loosened and removed.
Egyptian Mudbrick Palace of Beit She'an

After carefully removing the debris and mortar surrounding the bricks that will be replaced, they are lifted out of place.
Egyptian Mudbrick Palace of Beit She'an

The bricks are hoisted out.
Egyptian Mudbrick Palace of Beit She'an

Once the space is clear, it is filled with a mud-based mortar
Egyptian Mudbrick Palace of Beit She'an

The new bricks are set, and the wall is ready to ready to withstand a few more generations of visitors unable to resist climbing the walls for a better view of the Jordan Valley. (The mortar is wet, but will dry to match the surrounding brick)
Caesaria Fortress

The hole is wetted down and filled with mortar and small filling stones. Then the new ashlar is lifted up and pressed in.
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The visible mortar is smoothed down and squished into the remaining gaps. It is then sponged down with a dry sponge to give it a camouflaging texture. (final texture not pictured)
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A new ashlar must be carved out of matching sandstone to fit the empty space. The stone is carved using traditional tools as well as electric chisels.
Caesaria Fortress

A new ashlar must be carved out of matching sandstone to fit the empty space. The stone is carved using traditional tools as well as electric chisels.

About Conservation Practices at Mamshit:

The Byzantine church of Mamshit (a.k.a. Memphis) still retains its beautiful floor mosaics. However, they require maintenance and upkeep. The site manager is in charge of small repairs, such as filling lacunas and collecting loose tesserae, and keeping detailed records of conditions. Specialists are brought in for more advanced conservation.

For more information about Mamshit visit the Israel National Park Site.

About Conservation Practices at Beit She'an

"Tel" is a wonderful word in Hebrew that perfectly describes the landscape of Beit She'an. Roughly translated it is a mound created by layers of civilizations building on top of each other. If one were to cut into the hills of Beit She'an one would uncover a parfait of archeological sites from the Egyptians, Ottomans, Hellenistic Greeks, Romans, Byzantines, Ummayids, Mamluks, Crusaders, and Ottomons.

Atop one of the hills in the Beit She'an National Park are the remains of a governer's palace dating back to the Egyptian rule of Beit She'an (ca 1500 BCE).

The original walls of the former Egyptian governor’s house (dated to roughly the 12th century BCE) at Beit Shean were originally constructed of mudbrick, a common building material still used today. The lower layers of the original walls are still standing, and have been fortified with additional vertical layers of mud brick, in order to prevent erosion. However, these additional layers often require maintenance as they are susceptible to decay.

To learn more about Beit She'an National Park, visit the offical site.

About Conservation Practices at Ceasaria:

Further information coming soon!