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The Soleto stone is a hard limestone, extracted in the Apulian region, Italy, from historical quarries dating back to the early 1900s. Extraction of this stone is one of the main activities of Soleto (Lecce), a small village in the heart of Salento. The name Soleto already indicates its ancient vocation for stone working, in fact the name Soleto derives from syllithos, in Greek, a paved place. Examples of flooring made in the aforementioned stone can be found in most of the historic centres of the province of Lecce and in the Salento area.

"We are stone, living stone that resists steel, but, when you have marked it, it keeps eternal the imprint of your passion. If you strike it, it sparks, splinters, cuts; burns, yes the white lime, knead, binds. It is whetstone that wears you out, and refines you. The sacred limit of your house, grinds your daily bread ... It is an altar table. The northern wind splits it, because its matrix is ​​the sun! "

(Luigi Corvaglia, da FinibusTerrae)

Morphology
The extracted materials belong to the “Galatina dolomite” d geological formation from the Cretaceous, Mesozoic era. It consists of dolomitic limestones, made up of a double carbonate of calcium (CaCO3 ) and magnesium (Mg) with small quantities ofAl2O3, Fe2O3, Na2O, SO3, P2O5 and SiO2. The rock’s colour is hazel-grey with irregular fractures and is hard and compact with a microcrystalline and / or vacuolic appearance (relative to vacuoles, cavities present in part of the rock, to which they give this specific texture). At first glance it appears to the inexperienced eye as a set of layered boulders joined by earthy elements.

The succession represents the product of sedimentation in an internal carbonatic shelf: the outcrops that reflect prolonged exposure to hydrological and meteorological aggression are affected by relatively advanced karst. The formation is well stratified and the thickness of the strata varies between 0.5 and 2 m. The strata are always quite tenacious and resistant, even though they appear variously fractured and locally affect by karst.

The origin of the fracture systems, on which the networks of karst conduits are often set, relates to the stress and tensions, associated with tectonic activity, experienced by these rocks over the course of about 70 million years.

Raw material and production process


The original mining activity was carried out mainly by men with the help of very few mechanical means. In fact, the excavation took place mainly by the so-called “cavamonti”, whose role consisted in freeing blocks of rock from the outcrop in order to be able to work it by hand. Since the 1950s, the extraction of Soleto stone has taken place with the aid of mechanical machines (excavators) in open-cast quarries. Subsequently, mechanization extended to the stone processing, through the introduction of specialised machinery, including numerical control machines.

Over time, the increasingly intense exploitation of extraction sites, due to both the technological evolution and an increase in its demand, has led to a slow but gradual reduction in extraction opportunities. This is because the accessible outcrops of the Soleto stone are limited to a small geographic area and therefore an increase in production leads to the rapid exhaustion of the existing quarries while at the same time it is extremely challenging to identify new, viable, and unexploited extraction sites. Since 2010 there is only one surviving quarry.

The uniqueness of the Soleto stone derives not only from its intrinsic characteristics (colour grain texture, compactness, resistance) but also from the relative scarcity of the raw material, which is difficult to find and extract.

Uses


Soleto’s limestone, a substitute for marble and granite, is distinguished from other stone materials of Puglia due to its morphological variability, that makes each piece unique: shades of different colours, veins and mineralization break the monotony of each piece, whether it is a small element or large surfaces. This material is particularly suitable for the renovation of “Masserie”, typical southern Italy constructions, historical buildings or for the construction of traditional-style objects.

The most characteristic product is the “basolato”, a slab of limestone rock, of considerable weight and size (often 50x50 cm or 60x60 cm), used for road paving, initially used by the ancient Roman and adopted for centuries to pave the magnificent historic centres of Salento.

Thanks to its characteristics, it can be transformed into multiple uses: from street furniture to interior and exterior architecture, from handicrafts to urban and architectural restoration works. By applying numerical control processing techniques, it is possible to obtain sinks, shower trays and other furnishing elements.

Its low permeability and particular resistance to chlorine and to various atmospheric agents make it suitable for internal coverings, edges and flooring for swimming pools and fountains.