Herculaneum, precious Gem House reopens after restoration

At the Herculaneum Archaeological Park, the Gem House, one of the most important dwellings at the archaeological site, famous for its precious floor mosaics, reopens to the public after restoration work.

The Gem House, one of the most important dwellings in the Herculaneum Archaeological Park, famous for its precious floor mosaics, reopens today after restoration. This new visitor opportunity, the result of the experimental multidisciplinary open lab approach, accompanies the arrival of spring at the Park, continuing through June. The House of the Gem takes its name from the discovery of a gemstone with the image of Livia mistakenly attributed to this house, when in fact it comes from the House of Granianus, which was once part of a single large domus overlooking the sea, probably belonging to the family of Marcus Nonius Balbus, and features in the triclinium one of the most beautiful black-and-white geometric mosaics in the whole of Herculaneum.

Originally this dwelling was an integral part of the House of the Relief of Telefo, probably owned by the family of Marcus Nonius Balbus, which had an irregular layout, the result of continuous extensions to gain the sea view and the view of the Gulf. In the Augustan age the dwelling was developed on three levels over a good one thousand eight hundred square meters, representing the second largest dwelling in Herculaneum, and was connected to the Suburban Baths. In the last period of the city’s life, as part of a general restructuring, the gigantic residential complex was divided into three separate dwellings, creating the House of the Gem, which is located at street level, and another more modest house on the floor below, made independent thanks to an independent entrance at Porta Marina. Of this third dwelling we know the name of the owner, M. Pilus Primigenius Granianus, thanks to the discovery of a bronze seal. The Gem House preserves, in its stately quarter, very fresh characters of the plasters and in the floors. Certainly the house was inhabited, in its last days, by a distinguished family, who had among their guests a physician then famous in the imperial court of Titus, named Apollinaris, whose memory is consecrated by an irreverent inscription in the latrine, placed in the rustic quarter together with the kitchen. Like the other dwellings facing the sea, this house faces south with a series of rooms, including the triclinium, aligned on the loggia, now barely discernible.

The restoration

Herculaneum’s mosaics constitute one of the great riches of the site, covering most of the floors of the buildings’ interiors and exteriors. As many as 3,245 square meters of floor surfaces covered with mosaics in the Herculaneum Archaeological Park demonstrate what attention was paid to the aesthetic appearance of the domus and rooms of common use by the inhabitants of the ancient city. Apart from a few rare exceptions, the mosaic floors of the Herculaneum site can be traced back to the decorative phase of the IV Style, with black tesserae made of volcanic material (leucitite) and/or white marble, identified as palombino, arranged to create uniform monochrome and bichrome carpets with interwoven perimeter decorations, or embellished by central panels with geometric representations within them or, again, enlivened by polychrome marble inserts with predominantly quadrangular shapes, with various types of marbles: white, bardiglio, antique yellow, African, portasanta, alabaster and pavonazzetto.

The Gem House restoration project also included conservation work on the Houses of Pilus Granianus, the Relief of Telefo, and the House of the Deer. Thework on the pavements was necessary mainly to counteract active degradation caused by weathering and environmental factors (exposure to wind, rain, sunlight and freeze/thaw cycles, capillary rise of water), which required deeper restoration before being able to be part of the planned maintenance cycle that is already active at the urban scale. The mosaics underwent thorough cleaning and disinfection treatments, which allowed the recovery of tessellation, previously concealed by substantial biotic patinas. Portions of the flooring of the triclinium of the House of the Gem were also reconstructed, whose precious central decoration, divided into 21 geometric panels, had literally exploded.

The restoration also revealed traces of preparatory drawings of the geometric patterns of the large surfaces (sinopias) engraved by the ancient craftsmen who made them. Mosaics, in case of lack of mortar, or if partially not adhering to the support, can suffer detachments of individual tessellations or small fragments; the presence of biological agents and the growth of higher plants can also promote detachments of the tessellation and often accelerate the degradation of interventions implemented in previous restorations.

The team of restorers carried out all the necessary operations to restore the adhesion of the tessellations, eliminating macroscopic detachments and intervening in a sweeping manner to fill both superficial and deep voids, using suitable hydraulic injection mortars, as well as to reconstitute the cohesion of the tessellations, whose most superficial layer was compromised. The most relevant operation carried out in this restoration site was the repositioning in place of a multiplicity of tesserae that were lying in their rooms awaiting philological restoration work. In this way it was possible to stitch up large portions of the flooring, restoring uniformity of reading to the rooms and recovering, as in the triclinium of the Gem house, the precious central decoration, divided into 21 geometric panels. Another element of great value, recovered during this restoration work, is a floor with decoration in II Style, in colored limestone, among the oldest on the site, preserved in the House of Pilus Granianus.

The atrium of the House of the Gem was also the subject of a small archaeological essay in the impluvium, found in 1934, during the excavation of the domus under the direction of Amedeo Maiuri, in which the entire area of the atrium, damaged by Bourbon tunnels that ran through it at different heights, was recovered. The impluvium basin itself preserved only in one corner the marble facing, while the rest had already been removed in the 18th-century excavations. The essay made it possible to fix the time span and different phases of the structure’s life. In particular, the finding of Hellenistic pottery dates the area’s occupation for residential purposes to the first half of the second century B.C. Also of great archaeological interest has the evidence of different phases of the structure of the impluvium, which appeared slightly shifted from the original layout, as well as on the marble facing. Finally, the archaeological investigation revealed the transformation of the original basin into a fountain in the last documented phase. For conservation reasons, the project included the reconstruction of the basin and the replacement of the eaves, so as to improve the drainage of rainwater from the compluvium above and reduce stagnation on the pavement and moisture.

The restoration was financed with funds from the 2015 Stability Law, pursuant to Article 1, paragraphs 9 and 10, of Law No. 190 of December 23, 2014, for the year 2019, directed by Park staff with archaeological and conservation advice from the team of the Herculaneum Conservation Project, a private partner that has been working with the Herculaneum Archaeological Park since 2001, and carried out by the firm Casinelli Giuliano S.r.l.

The statements

“The insula Orientalis I, in which the House of the Gem is located,” says Francesco Sirano, director of the Archaeological Park of Herculaneum, “has mosaics of exceptional value: with this project, which also involved the Houses of the Relief of Telefo, Granianus and the Deer, we have restored the most delicate mosaics of the site. In addition, the painstaking work in the House of the Gem has made it possible to completely recover the floor surfaces in such a way as to allow visitation, albeit in an experimental mode. We are creating the conditions to expand the tour in the archaeological site and share elements and spaces of the ancient city for too many years removed from direct experience by visitors. The goal of our work is to enhance the site for an ever wider public that is curious and aware of the cultural values and delicacy of UNESCO heritage.”

Jane Thompson, Project Manager of Herculaneum Conservation, recalls that “The long journey that today’s opening of the Gem House represents is a fine tribute to the ’site-wide’ approach that has been in place for more than 15 years thanks to the partnership with PHI, which, instead of supporting exhaustive projects on a few domus, has improved and continues to improve the overall condition of the entire site. Working in this way, and thanks to restoration campaigns like this one on the mosaics, leads to such important outcomes as the reopening to the public of rooms that have long been foreclosed.”

The Gem House opens daily from 9:30 a.m. to 1 p.m. (Wednesday is the Park’s weekly closing day). Access to the Gem House is allowed to groups of up to 20 people at a time. More info can be found at www.ercolano.beniculturali.it.

Herculaneum, precious Gem House reopens after restoration
Herculaneum, precious Gem House reopens after restoration