## 1 Introduction  
The prevention of waste production and maintenance of natural resources as long as possible in the economy are some of the principles promoted by the action plan for the Circular Economy of the European Green Deal [1].  
According to available data [2], the annual granite blocks market ranged from 8 \(\times\) 10\({}^{6}\) to 9 \(\times\) 10\({}^{6}\) tons in the period 2015-2022. Wastes produced during granite block processing result from sawing, shaping, and polishing of granite blocks and represent approximately 38% \(w/w\) of the total raw stone [3]. The sawing of granite blocks into slabs generates coarse fragments (scrap), sawdust, and granite sludge (GS). The GS, which is characterised by an average moisture of 23% \(w/w\), corresponds on average to 24% \(w/w\) of the total weight of the processed raw block; thus, an additional amount of 2.0 \(\times\) 10\({}^{6}\) tons of GS are expected to be produced worldwide annually. GS is, in most cases, disposed of in landfills. Due to the very small particle size of its constituents, GS can be responsible for environmental contamination (air, soil, and water) and subsequent public health problem if unproperly managed [4].  
The GS Is composed of water, fine, coarse granite wastes, metal parts resulting from the wear of cutting tools, flocculant, and grease residues. Based on GS mineralogical, chemical, physical, and mechanical properties, several authors have studied the GS potential for being valorised in the production of (i) bricks and tiles [5; 6; 7; 8], (ii) pigments for the ceramic industry [7], (iii) fired clay bricks [9; 10], or as (iv) substitute for fine sand in concrete mixtures [11], dry mortars [12], or as cement as pozzolan [13]. Recent findings have suggested the potential of GS as (v) a substitute for silica flour for oil-well cementing [14]. Among these different valorisation pathways, the use of GS as a substitute for feldspar in the ceramic industry and fine inert materials in concrete mixtures seemed to be the most promising ones [4; 5; 6; 11; 15; 16; 17; 18].  
Over the technical aspects, to guarantee its environmental and economic sustainability, the choice for a GS valorisation pathway must be integrated with the assessment of environmental impacts and cost analysis associated with the option selected. The Life Cycle Analysis (LCA) [19] and Life Cycle Cost (LCC) [20] are consolidated methodologies able to support and drive the selection of the most suitable valorisation pathways, quantitatively measuring the advantages and disadvantages of each scenario studied, according to models based on scientific consensus [21; 22] and on the most recent environmental approach.  
The present study has the triple aim of assessing the technical feasibility, the environmental advantages, and life-cycle cost as well as the cost-benefits associated with the strict valorisation of GS (i) as a substitute for feldspar in ceramic paste or (ii) as a substitute for fine-medium inert filler in structural concrete mixtures. The novelty of this work lies in the integration of the traditional laboratory experimental tests with environmental considerations properly harmonised with LCC analysis, providing fundamental information for future strategic decisions and investments of GS valorisation in a circular economy perspective.