The Montorfano and Baveno granite ore bodies are located in the Lake District (VCO-NE Piedmont). They were and are still quarried as dimension stones, with a consequent production of a huge volume of “waste.” In 1995, an Italian company (GMM S.p.A) decided to invest in the valorisation of granite quarry waste as a secondary raw material. An in situ geological prospecting was carried out in order to evaluate the characteristics of the material and the thickness and volume of the useful disposal sites that could be used (by means of geophysical surveys). As a consequence of the field work, the amount of quarry waste was estimated as nearly 2？Mm3. Chemical analysis was carried out on 75 granite samples, in order to individuate the Fe2O3 grade: from 1.321–2.593% of the original waste to 0.160–0.228% after the “dry process” treatment. Three different detailed maps that show the typology, the locations, and the quality distribution of the material in the dumping areas have been drawn up. 1. Geological Setting The main quarry disposal sites, the subject of the present research, are located in two different areas: the Sengio and Ciana Tane-Pilastretto dumps, which are located on the southern slope of the Montorfano Massif, while the Braghini site pertains to Monte Camoscio, on the right side of the Toce River (Ossola Valley) (Figure 1). Figure 1: Geographic context of the studied area. The main image shows the satellite orthophoto of a portion of Massiccio dei Laghi batholith. In the northern part of the map (Montorfano area), it is possible to individuate both the white granite (represented by grey stripes) and the green granite portion (green Mergozzo type, represented by green stripes). The orange area defines the Baveno-Mottarone pluton. Furthermore in the image the exploited quarry dumps (red points) are represented and the ancient quarry waste areas, potentially useful for a future valorisation (yellow points). The two granitic plutons belong to the Hercynian Magmatic belt, which is located between the Ivrea-Verbano zone and the Serie dei Laghi unit. These units pertain to the South Alpine system basement and are situated to the south of the Insubric line. The Permian granites, Graniti dei Laghi, consist of nonmetamorphosed to weakly metamorphosed rocks [1, 2] and constitute an elongated SE-NW batholith, between the Biella-Valsessera and Val d’Ossola zones. This batholite is formed by singular plutons which develop a narrow contact aureole [3] in the Scisti dei Laghi and the Strona-Ceneri formation. The batholith is composed of five plutons:
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