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• An approach for the conservation of waterlogged wood veneered in ivory is described. • Dual evaluation performed on samples prepared in laboratory and on one original piece. • Laboratory samples were artificially degraded putting them in contact with brown rot. • Drying conditions were highly important for the success of the entire treatment process. • Approach applicable where suitable conservation methodology needs to be set-up. This work describes how a conservation method making use of aqueous solutions of lactitol and trehalose (9:1) was chosen to treat several elements of wood furniture veneered in ivory carved in bas-relief and preserved in waterlogged condition. These elements were discovered during the excavations carried out in Villa dei Papiri, the most famous of the luxury villas of Herculaneum. The approach described was based on a dual evaluation. It was carried out: (a) on probe wood specimens produced in the laboratory capable of simulating both the impregnability by consolidants and the deformation of decayed waterlogged wood; (b) on one archaeological element belonging to the original furniture, representative of the material to be treated. The probe specimens produced in the laboratory were artificially degraded by placing them in contact with the brown rot fungus Coniophora puteana , in order to obtain a material of variable decay, similar to that of the original archaeological furniture elements. Three experimental factors were considered when treating probe specimens: (a) the type of substrate, (b) the initial and final consolidant concentration and (c) the drying regime. Three types of substrates were considered: specimens covered with a polycarbonate sheet to simulate the ivory veneer and wrapped in gauze; specimens only wrapped in gauze; and naked specimens, that is, with no obstacles for consolidant penetration. Considering consolidant concentration, the probe specimens were impregnated by full immersion, increasing the concentration of lactitol/trehalose in four combinations: from 15 to 50%, 15 to 60%, 30 to 50%, and 30 to 60%. Last, three drying regimes were considered: 50 °C in an oven, 30 °C/35% RH and 20 °C/65% RH. Results showed that probe specimens whose impregnation started with 30% consolidant in the solution and finished in 60%, and dried under 30 °C and 35% RH exhibited limited volume variations after drying equivalent to those obtained by drying at 50 °C. Drying conditions were important factors in the success of the entire treatment process. As was consolidant uptake, in relation to the extent of decay of the archaeological material. Moreover, the presence of the physical barriers simulating the existence of the ivory veneers and gauzes did not disturb the efficacy of the treatment, as long as sufficient time was given to allow the water-consolidant exchange process to be completed. In the end, the treatment conditions selected on the basis of these probing tests, that is, start with initial concentration of 30%, final concentration of 60%, and drying at 30 °C/35% RH, showed to be successful for treating the representative element of the archaeological furniture. [ABSTRACT FROM AUTHOR]

This paper constitutes an attempt at using FT-IR spectroscopy for the dating of historical and artistic artefacts made of poplar wood. It was decided to do the tests only on poplar (Populus spp.) to reduce a part of the typical wood variability, while poplar was chosen because it is widely present in Italian heritage, such as panel paintings, statues and furniture, and these objects cannot be dated by dendrochronology; also because 14C methodology has major limitations. Poplar artefacts from the fourteenth to the nineteenth century were selected, dated by means of documents, by attributions, or stylistically. In addition, recent poplar samples were selected as a reference. Wood flour were taken from the selected samples, discarding the surface layers that could have been influenced by oxidation phenomena. Before taking measurements with FT-IR, the wood meal was dried and the chemical extractives were removed. The results show the presence of a time-related trend, but the time factor is certainly not the only one that causes the variations within the spectra. After a discussion, it is therefore considered that the results do not allow at the current state to definitely produce a reliable reference for dating poplar wood artefacts through this methodology. [ABSTRACT FROM AUTHOR]

Highlights • The wooden foundations of Ponte di Rialto were analysed in order to determine the tree species used for its construction and to examine the timber's present-day physical and mechanical properties. • The foundations underwent micro-morphological, physical, chemical and mechanical analyses. • The footings of the bridge's foundations, mostly consisting of alder wood, were shown to be in a good condition generally. • Two periods of construction were determined. The later dating corresponds to the construction of the stone bridge that still exists today, while the other period probably refers to the foundations of the initial Ponte della Moneta. Abstract The wooden foundations of Ponte di Rialto (Rialto Bridge), the oldest and most famous of the four bridges spanning the Grand Canal in Venice, Italy, were analysed in order to determine the tree species used to construct the foundation, to examine the timber's present-day physical and mechanical properties and to identify construction periods. The material recovered during geotechnical surveys underwent micro-morphological, physical, chemical and mechanical analyses. The radiocarbon method was used for dating purposes. The footings of the bridge's foundations, mostly consisting of alder wood, were shown to be in good overall condition generally. A comparison of normal and polarised light images of wooden cross-sections showed abundant crystalline cellulose within the cell walls, indicating that the state of conservation of the waterlogged samples is very close to that of sound alder wood. Only one alder sample showed signs of severe bacterial attack, mostly concentrated in the fibre cell walls. Radiocarbon dating identified two distinct construction periods. One sample dates to 1570 AD ± 85, whilst another dates to the year 960 AD ± 59. The later dating corresponds to the construction of the stone bridge that still exists today. The earlier period, around the year 1000, likely refers to the foundations of the first bridge, built after several pontoon bridges, and corresponding to the initial Ponte della Moneta. [ABSTRACT FROM AUTHOR]

Abstract The study of an ancient musical instrument should take into account various approaches, which include historical sources, study of materials and dendrochronological analysis. Very often, an ancient musical instrument has been subject to repairs, substitutions and restorations that have modified its original setting. This study takes into account the "Mango Longo guitar", a masterpiece of 17th century Neapolitan art. It has been analysed from a historical, organological and xylo-chronological perspective to investigate and describe the cultural context of its creation, the wood species used for its construction and various restoration works to which it has been subjected. The Mango Longo guitar belongs to the typology of the Baroque guitars of the seventeenth century, attributed to the lute-maker of German origin Magnus Lang, from which the name derives. The most recent tree-ring identified on the instrument belly is dated dendrochronologically to 1737, terminus post quem. This means that the actual soundboard may be considered a replacement, due to a restoration in the first half of 18th century. The analysis of dendroprovenance of the actual soundboard shows strong analogies with Italian production of the period and identifies the probable sources for wood as being in the Alps. Our results confirm the intensive and well-organized trade of valuable timber used for musical instruments at that time. [ABSTRACT FROM AUTHOR]

The analyses to determine the state of preservation of waterlogged archaeological wood follow three different directions: anatomical analyses, physical evaluation and chemical characterisation. Physical parameters (densities and moisture content) are the ones most frequently found in the specialised literature. The measurement of moisture content is normally referred as maximum water content (MWC) in the case of archaeological wood in waterlogged conditions, because wood has been long-time preserved by the lack of oxygen in waterlogged conditions. Aim of the paper is the comparison of three pre-measurement treatments in the calculations of MWC: without any vacuum-pressure treatment, after 300 mbar vacuum pressure and after 50 mbar impregnation in water. The evaluations were performed on 240 samples of waterlogged archaeological wood coming from different excavation sites and including different wood species (both hardwoods and softwoods) in different state of preservation, from low to very high decay. The three tested methodologies to measure the maximum water content on waterlogged archaeological wood provided substantially equivalent results. Nevertheless, a deeper analysis of the results showed that the MWC values of 300 mbar impregnations were rather low compared to MWC standard measurements. Thus, this impregnation was a little bit harsher, causing most probably an anatomical damage on a portion of most degraded samples. The opposite result was obtained after the 50 mbar impregnation procedure. In this case, the MWC values were slightly higher. This means that this treatment seemed to be more effective in subtracting even the smallest air bubbles trapped inside waterlogged archaeological wood samples. Some suggestions on how to measure MWC on waterlogged archaeological wood are detailed at the end of conclusions. [ABSTRACT FROM AUTHOR]

Paper deals with the scientific identification of timbers utilised for the production of the sculptures preserved within the collection of the National Museum of the “Palazzo di Venezia” in Rome, Italy. After a brief description of the Museum and its sculpture collections, and, more specifically, the wooden sculpture collection which is the largest in Italy, the sampling of the artwork is discussed and described, together with the methodology used for the identification of wood species following the Italian standard UNI 11118:2004. The 12 identified timbers are listed together with their distribution within the cultural provenance of the sculptures. The discussion deals with the timber species utilised by the artists from the four cultural European provenances most represented within the collection: Italy, Alps, central-southern Germany and Lowlands around the Rhine delta. In the different Italian regions, several wood species were utilised and among them mostly poplar and limewood, while the alpine sculptors mostly used Swiss stone pine and the German artists, limewood. Finally in the Rhine delta, most of the sculptures were made out of deciduous oak. [ABSTRACT FROM AUTHOR]

This paper outlines the physical characterisation of findings of woods from the excavation of the Etruscan–Roman ancient harbour of Pisa. The physical characterisation deals with measurements of wood density, shrinkages and maximum water content. The measurements are performed with a methodology specifically set up for the archaeological wet material, not applicable as standardised international methodologies. Physical characterisation is necessary to measure the wood decay, through a useful decay index, and to define the consolidation strategies for the recovery of the wooden findings, for their conservation and enjoyment. Results confirm the high decay of wood samples, probably due to the almost complete loss of the cellulose fraction of the cell walls, shown by the very low basic density (average value less than 0.2 g/cm3) and the high water content (more than 500%). The parameter of the residual basic density seems less useful for the identification of the consolidation strategy. [Copyright &y& Elsevier]

• EDTA-2Na, EDTA-4Na and citric acid used to extract iron in oak wood (Quercus spp.). • ESEM, FT-IR and DMA used to characterise samples after the extraction treatments. • Alkaline agents have an impact on both chemical and viscoelastic characteristics. • Modification and loss of hemicelluloses increases the viscous behaviour of treated wood. • Results are generalizable to the various wood treatments where high pH is adopted. The process of extracting iron from waterlogged wood was simulated on non-degraded oak wood (Quercus spp.) with the aim of evaluating the effect of three levels of pH (acid / close to neutral / alkaline, obtained using three products normally used to extract iron) on both the composition and the viscoelastic mechanical properties of wood samples. The three products were disodium-ethylenediaminetetraacetic acid (EDTA-2Na), tetrasodium-EDTA (EDTA-4Na), and citric acid, and they were used at different concentrations and different extraction durations. Environmental Scanning Electron microscopy (ESEM) was used to observe the microstructure before and after extraction, ATR-FTIR was used to analyse the chemical composition and Dynamical Mechanical Analysis (DMA) was used to assess the storage and loss moduli and the loss factor of samples after treatment. Mass loss measurements after treatments were also carried out. The results indicated that chelating agents inducing alkaline conditions could have an impact on both chemical and viscoelastic characteristics of wood, whereas neutral or acidic conditions did not appreciably affect the considered characteristics. The observed effects are related to modifications of hemicelluloses composition (with partial mass loss of wood), which provoked a clear increase of the viscous behaviour of the treated material. These modifications were only limitedly and indirectly detectable using the other considered techniques. Being induced by the obtained alkaline conditions, present results are generalizable to the various treatments where high pH is adopted, and hence not only limited to the iron removal process. Thus, based on the knowledge attained in this research, conservators can be aware of the potential impact of these treatments on the wood structure, and this should help in gaining greater control over this process. [ABSTRACT FROM AUTHOR]

Multidisciplinary diagnostic methods were applied to evaluate the preservation state of waterlogged archaeological wood (WAW) from ancient Chinese shipwreck Nanhai No.1. The characterisation combines micromorphological, physical, and Fourier transform infrared (FTIR) analyses to overcome limitations of using a single analysis. The micromorphological analysis used the whole-slide imaging (WSI) method to identify wood species and determine the decay class. The collected samples were graded as Class 2 (moderate decay) or Class 3 (severe decay). Bacterial and fungal attacks on wood tissues were evident, and the decay pattern of erosion bacteria (EB) was verified. The maximum water content obtained from the oven-drying and freeze-drying methods confirmed that the micromorphological features can be used to grade the decay class. In tandem with hierarchical cluster analysis, FTIR measurements classified four clusters, including moderate and severe decay groups. FTIR also revealed that the chemical alteration of WAW was mainly due to the depletion of polysaccharides. Increased knowledge of WAW degradation and feasible diagnostic methods are beneficial for further conservation strategies. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the diagnostic analysis performed on the different timber structures of the Nativity Church. The surveys were performed in agreement with the Italian standards UNI 11161:2007 and 11119:2004. The uniqueness of some structures made it necessary also the analysis and description of structural typologies. The results allow describing the different timbers utilised, the state of preservation, mechanical and biotic decays and finally to determine the present strength of each wooden element, obtained through the combination of the evaluation of the defectiveness and the measurement of the residual sections. The results of the diagnostic survey will influence the design of the structural restoration and of the maintenance operations. [Copyright &y& Elsevier]

Wood identification is a basic information that should interest any wooden artefact. This typically involves invasive sampling, but sometimes sampling is unattainable either because of the object typology or because it is difficult to obtain authorizations. In the present study, reflected light microscopy potential as a non-invasive identification tool for wooden cultural artefacts is assessed on a number of marquetry furniture and small wood carvings. In more than one half of the 13 examined cases accurate wood identification was possible, while the remaining cases yielded information of diagnostic value, making it possible to exclude several potential candidate species. In a number of cases the use of optical filters improved the visibility of character states. Shape and orientation of surfaces influenced the visibility of microscopic characters. The study confirms that reflected light microscopy is a valuable tool for non-invasive wood identification. In many cases it is able to support accurate identification, in others it can anyway provide important information, useful to help decision about supposed species, or to limit the invasiveness of possible further analysis by addressing them on specific features. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the work is to set up a methodological approach to verify the effectiveness of the treatments of decayed waterlogged archaeological wood and to point out the proper thermo-hygrometric conditions for its preservation after treatment. The treatments were performed on wood samples of maritime pine (Pinus pinaster Aiton), oak (Quercus sp. caducifolia), elm (Ulmus cf. minor) and strawberry tree (Arbutus unedo L.), obtained from stems pertaining to the original vegetation found in the excavation site of the Ancient Ships in Pisa (Italy), and dated from seventh century BC to second century AD The utilised products were: Polyethylene Glycols (PEG) of various molecular weights, a Polypropylene Glycol (PPG 425), Trehalose (α-D-glucopyranosyl-α-D-glucopyranoside), and their mixtures, and also a Hydroxypropylcellulose (Klucel). The main objective to be pursued by the treatments was considered the stabilisation of the original size and shape of samples. The various steps of this approach were: the execution of a preliminary diagnostic survey on untreated samples; the characterisation of treatment solutions ‘as such’ to establish the property to be monitored during the treatment; the evaluation of the main physical characteristics of wood after the treatment were determined. Among the latter, the coefficient of dimensional stability during the exposure to a series of selected thermo-hygrometric conditions and the retention of consolidants after the treatment. These two measurements allowed the definition of the ‘efficacy of a treatment’, φ T , a new parameter firstly utilised in this work. It measures the stabilisation capability of the percent unit of retained product, and its value permits to put in evidence the consolidants that stabilise wood with the lowest amount of product. Conversely, it was not possible to measure the Anti-Shrink Efficiency (ASE), one of the most utilised parameters for the evaluation of treatments, because of the serious distortions and fractures observed in all the heavily degraded untreated samples. [Copyright &y& Elsevier]

Huaguangjiao І is a Chinese ancient wooden shipwreck of South Song Dyansty (1127–1279 AD). Wood samples from Huaguangjiao І were analyzed in order to evaluate the preservation state of the waterlogged wood. Samples were studied from the anatomical, physical and chemical point of view. Thin slides of cross and longitudinal sections from samples were observed by optical microscope, micromorphological decay was classified into class 3 or class 4 according to the anatomical characters. Water content and basic density were measured. Maximum water content (MWC) of the wood samples is between 300% and 600%, residual basic density is about 50%. The proportion of the α-cellulose decreased to 25% of the normal value, and the content of the ash increased greatly. These results indicate the degradation of the wood is very high. In addition, there is a plenty of inorganic deposit in the wood structure. The inorganic compounds deposited in wood samples were analyzed by XRD and ICP qualitatively and quantitatively. The morphology and composition of the inorganic deposit was characterized through SEM-EDS, the majority were iron sulfide, including pyrite and marcasite (FeS 2 ), and fluorite (CaF 2 ). [ABSTRACT FROM AUTHOR]

Archaeological excavations in the docking site of Pisa (Central Italy) unearthed several shipwrecks which dated back to the Roman time, from the Republican to the Imperial periods. The recent identification of the woods used for building ships D, E, H, I and P, in addition to data of the previous analysis of ships A, B, C, F, L, revealed the utilization of 18 different taxa . Wood from oaks, both deciduous and evergreen, is mostly represented. 6 different softwood timbers, mostly from maritime and umbrella pine, were also largely used. Some of the hulls were entirely realized with hardwoods, others with softwoods or using a combination of softwoods for planking (mostly pines) and different hardwoods for the frame. The selection of timber indicates a skilful knowledge of the technological properties of the different woods and their suitable utilization in the Roman vessels. The use of woods largely available in the territory surrounding the Pisa docking site, as demonstrated by pollen analysis, does not necessary indicate the local production and/or provenance of the ships, given the spread of the identified wood taxa throughout the North Mediterranean area. [ABSTRACT FROM AUTHOR]

Abstract: Forty years ago in a xxth-century church in Torino, a small fire partially burned some of the decorative external boards of the sound-box of the organ. The focus of this present work was to find a treatment able to consolidate partially burnt wood in dry conditions, in which the external charred layer would be lost if not well preserved because of its incoherence. The product had to be applied onsite on an architectural structure intended to be reused again (and not simply exhibited). This circumstance is rarely encountered in the conservation of wooden Cultural Heritage. The efficacy of treatments was evaluated on the basis of a suitable and original experimental methodology, which took into account both the immediate and long-term behaviour of the various tested products. Although the opportunity to carry out this work came from a real case, both the selected product and the set up evaluation methodology have a general validity and they can be effectively used in other similar situations in which a slight antipowdering effect is required for treatment. [Copyright &y& Elsevier]

One of the problems in marketing the wood of Prosopis and Acacia is the lack of standardization of its qualities. The aim of this paper was to obtain a preliminary detection of some properties of the wood of four species of the genus Prosopis and one species from Acacia grown in Argentina. To accomplish this objective, the content of extractives and some physical and mechanical characteristics were analyzed. The density ρ12 of all the species indicates that these woods range from heavy to very heavy (⩾0.69g/cm3). The total volumetric shrinkage values are low, less than 10%, for all species. The parallel compression strength and the shear strength for all the species indicate a very resistant wood (⩾46.93MPa and ⩾18.35MPa, respectively). Brinell hardness was higher than 5kg/mm2 in all cases. The species with less content of extractives is P. ruscifolia (approximately 9% of anhydrous mass) whereas A. aroma was the one with the greatest content (approximately 25% of anhydrous mass in the heartwood). [Copyright &y& Elsevier]

Abstract: The most frequent dating methods of wooden artefacts are briefly introduced and discussed. Each of them shows merits and shortcomings. Therefore, an integrated approach of different techniques sometimes allows overcoming specific difficulties. The dating of a wooden support of a precious panel painting through a detailed xylological analysis and the joint use of dendrochronological and radiocarbon dating techniques is proposed. While any single dating technique demonstrated ineffective, the simultaneous use of several approaches in the study of the artefact led to excellent results in terms of both reliability and resolution, thus contributing to the inclusion of this painting in a specific historical period. On the basis of the performed dating, supported by the features of the panel and by a chemical-stratigraphic analysis of paint fragments, the artwork cannot be attributed to Cesare da Sesto. [Copyright &y& Elsevier]