*1.3. Objective and Originality of the Research*

The ornamental stone sector, which through its production and extraction generates about 40 to 60% of waste, was investigated [19]. It is estimated that there is a loss of 84% from the beginning to the final production of commercial dimension stone slabs. As Brazil is one of the largest ornamental stones producers, there is still a lack of concern to avoid waste and a neglect with the waste destination, even though companies in the sector are responsible for developing projects for their recovery and reuse [15].

Quartzite waste was obtained as raw stone, with a massive structure and coarse grain, usually cracked and milk white in color. The material is petrographically called "Quartzolite or quartzites" due to the presence of more than 90% silicon, and they are classified as "Class II B—Inert" wastes.

Vegetable oil-derived polyurethanes have been extensively studied in recent years, as a non-polluting alternative to replace petroleum-derived polyurethanes [20]. The development of new polyester polyols and prepolymers derived from fatty acids cause this polyurethanes class to present themselves with different chemical, physical, and mechanical properties, in addition to being from a renewable source [20]. It is important for the development of a new material such as artificial stone to use biodegradable natural resin and quartzite residue.

Epoxy resins are thermo-rigid materials widely used in adhesives, matrices for composites, electrical materials, and materials for coatings, among other applications, as well as in the production of artificial stones, because of their excellent adhesive, mechanical, thermal, and electrical properties [21]. For these reasons, it is important to investigate the influence of both types of synthetic and biodegradable resins on the development of artificial stone.

This new alternative, in addition to possibly reducing raw materials costs since the waste is costless (excluding its transportation costs), would also transform the waste back into raw material. The polyurethane resin used as a binder originates from castor oil, a renewable vegetable source, and together with the inert waste of natural quartzite stone, it allows the manufacture of a totally ecological and sustainable artificial stone [20].

Epoxy resin is an excellent thermoset polymer to be used as a binder in artificial stone development. The mechanical properties can be accentuated, providing an optimal adhesion to the quartz waste particles. As the epoxy resin is characterized by good chemical resistance, it will generate an environmentally harmless artificial stone with adding value to wastes that would be discarded while reducing the production costs [9].

This work's main goal is to compare the development of artificial stones from quartzite waste, using epoxy and plant polyurethane resins as binders, with good physical and mechanical properties. This waste is also compared with the performance of our artificial stone and with other artificial stones in order to confirm the technical feasibility of producing these novel sustainable materials with economic potential.
