Geochemical Data of Maiolica Chert from Central Italy for Provenance Studies

Context

Provenance studies on lithic raw material represent a key mean of advancing our understanding of Prehistoric human mobility and connectivity as stated by previous research e.g., [1].

In fact, archaeological cherts provide an excellent proxy, owing to the abundance and wide distribution of chipped stone artefacts. Determining their provenance enables to trace human movements across the landscape from sites to sources, thereby shedding light on various aspects of ancient societies such as, among others, procurement strategies, territorial behaviour, social organisation and exchange e.g., [1, 2, 3].

Despite the widespread availability and distribution of chert, the investigation of lithic raw material sourcing in central Italy remains challenging. However, the region is rich in chert-bearing deposits as part of to the Umbria-Marche succession [4]. Previous research by Carletti et al. [5] addressed this issue by publishing the first pXRF-based characterization of Scaglia Bianca Fm. chert from central Italy, specifically from Abruzzo, Latium, Marche, and Umbria regions.

The dataset presented in this work is part of the lithotheque SiliROck, stored at the Department of Antiquities of Sapienza, University of Rome. It constitutes the updated continuation of Carletti et al. [5, 6] with the purpose of disseminating the SiliROck lithotheque to the broader research community and creating a user-friendly infrastructure for sharing data.

The dataset is accompanied by a photographic archive that is freely available for consultation. Chert surfaces have been cleaned and immersed in water and microphotographs have been acquired at different magnifications (10x, 20x) using a Leica EZ4W stereomicroscope with built-in LED illumination and CMOS camera.

The present work is the first attempt to make the characterization data open, accessible and reusable by researchers interested in provenance investigation, regardless of context and chronology.

Spatial coverage

The dataset shows part of the SiliROck lithotheque, and the characterization data acquired. It displays the characterization data of 97 chert samples from six different sources, belonging to the Maiolica Fm., located in central Italy: in Abruzzo (1), Latium (2) and Umbria (3). Sampling locations are shown in Figure 1.

Figure 1

Description: central Italy (mainland). Location names are displayed in Figure 1.

• Northwestern boundary: 29.2887 E; 47.44820 N

• Northeastern boundary: 40.2231 E; 47.46985 N

• Southwestern boundary: 29.9692E; 46.61458N

• Southeastern boundary: 33.4181E; 46.61768N

Temporal coverage

The dataset has no temporal coverage and can be used regardless of chronology.

Steps

Geochemical data have been acquired on fresh fractures with a NITON XL3t 900 portable ED-XRF spectrometer (Thermo Scientific) equipped with an Ag target (2 W). The spot size was approximately 3 mm in diameter, and the resolution of the detector was lower than 160 eV. At least three measures on the matrix of each sample were acquired and the mean values were reported in the table. To quantify both light and heavy elements, a total of 120 s (real time) was used. Each measurement was performed using three different spectrometer setting in order to enhance the fluorescence in the low, medium and high energy range: (I) 60 s at 40 kV and 50 μA (main range, from 0 to 40 keV); (II) 30 s at 20 kV and 100 μA (low range, from 0 to 10 keV); (III) 30 s at 50 kV and 40 μA with a Mo filter (high range, from 10 to 40 keV). At the end, a total of 11 elements were detected and quantified in the chert samples: Sr, Rb, As, Zn, Ni, Fe, Ti, Ca, K, Mn and Ba. To assess the analytical performances of the spectrometer, the certified reference material TILL-4 (The Canadian Certified Reference Materials Project) was analysed. The recovery ranges between 87 and 117%, depending on the element, and the relative standard deviation is lower than 2% for all the elements with the exception of Ni (25%). The limits of detection (LODs) were determined as three times the standard deviation of the replicated blank signal (3σ method), and they are 1 mg/kg for As, Rb and Sr, 8 mg/kg for Fe, 10 mg/kg for Mn and Ni, 50 mg/kg for K and 68 mg/kg for Ba.

The XRF spectrometer was calibrated using a set of geological Service of Analyzes des Roches et des Minéraux (SARM, CRPG-CNRS, Vandoeuvre-les-Nancy, France) standards, including those in particular silicate rocks.

Sampling strategy

The sampled primary outcrops are located in the central sector of the Apennine chain (Figure 1). The Maiolica Fm. is part of the Umbria-Marche basin, characterized by shelf to deep-water pelagic domains [4, 7]. The term Maiolica, or Majolica, has been in use since the 19^th Century referring to a carbonate unit from Lombardy (northern Italy) of Jurassic-Cretaceous age. All over Italy, Maiolica is also known as “Biancone” (Veneto, northern Italy), “Calcare rupestre” (Tuscany, central Italy) and “Lattimusa” (Sicily, southern Italy). It exhibits white limestones and micritic limestones, organized in beds and layers; localized intercalations of finely detrital limestones occur.

Sampling involved six primary sources. Samples have been collected systematically at fixed and regular distances of about 1 m, both vertically and horizontally, to gain a representative overview of chert variability within each outcrop. At least 15 chert samples per outcrop were collected. The output of the sampling activity is shown in Table 1.

1. CAT01. Primary outcrop identified on the foothills of the Catria Mt (Pesaro Urbino prov., Marche region), near the Umbria-Marche border (Figure 2.5). It exhibits well-layered fine micritic limestone strata with grey chert cropping out in nodules and layers. Nodules range from small to medium size and layers are few centimetres thick. Chert is light to dark grey and exhibits a good knapping potential. Recently, a landslide destroyed the deposit cropping out along the route leading to the Chiaserna village (Marche).

2. MF03. Primary outcrop. Exposed on the central sector of Montagna dei Fiori (Teramo prov., Abruzzo region) the outcrop is characterized by well-layered limestone thick beds (30–80 cm) with nodules and layers of dark grey chert. Nodules are abundant and measure up to ten centimetres of diameter (Figure 3). Samples e.g., nodules and slabs, in primary positions have been collected, although the presence of rockfall netting prevented a systematic sampling. The unit formed during the Barremian (Neocomian)-Tithonian [8].

3. MP01. Primary outcrop identified on the foothills of the Pellecchia Mt (Rieti prov., Latium), near the municipality of Monteflavio. It exhibits well-layered fine micritic limestone strata with grey chert nodules (Figure 2.1). Chert was collected on the karst plateau, cropping out as nodules in the exposed bedrock. Nodules are small- to medium-sized and exhibit poor knappability. The formation originated during the Tithonian-Lower Aptian [9].

4. MTM01. Primary outcrop located on the foothills of the Torre Maggiore Mt, near the village of Cesi (Terni prov., Umbria region). The outcrop is ca. 5–6 m wide and is characterized by well-layered fine micritic limestones of whitish colour (Figure 2.3). Grey chert occurs in layers and nodules with poor knappability. Samples in subprimary position were documented. The formation deposited during the Barremian-Tithonian [10].

5. SP01. Primary outcrop. The unit is composed of white to light grey, very fine-grained micritic limestones, generally thin- to medium-bedded (Figure 2.4). Chert samples were collected near Spoleto, in the Nera Valley (Umbria region). Chert is light to dark grey and slightly tectonized, occurring in layers and nodules of small-to-medium size. The unit formed during the Early Cretaceous (Tithonian-Barremian) [10].

6. TER01. Primary outcrop identified along the Valnerina route (Umbria region) (Figure 2.2). It exhibits the same features of SP01, with well-layered fine-grained micritic limestones interlayered with chert strata. Chert is greyish and crops out in medium-to-thick layers; however, it exhibits a bad knapping potential due to the tectonization process affecting the unit. The age of the formation is Tithonian-Barremian [10].

Figure 2

Figure 3

Quality Control

The dataset has been checked by all authors.

Object name

SIlirock_Maiolica_Chert_Dataset.csv: the dataset containing chert information and geochemical data.

Silirock_Maiolica_Chert_Archive.zip: photo archive as a compressed file containing .JPG images. Images have been acquired using a Leica EZ4W stereomicroscope with built-in LED illumination and CMOS camera. Chert fresh surfaces have been cleaned and immersed in water.

Data type

Processed and primary data. Physical chert samples are stored at the Department of Antiquities of Sapienza, University of Rome, and are accessible via request.

Format names and versions

.csv, .zip, .JPG

Creation dates

20/11/2025–26/01/2026

Dataset Creators

Elena Carletti (ORCID: 0000-0003-4653-9231)

Giacomo Eramo

Ignazio Allegretta

Language

English

License

Creative Commons Attribution 4.0 International (CC BY)

Repository location

10.5281/zenodo.18327835

Publication date

26/01/2026