USCS Soil Classification Dataset of tailings

This dataset compiles the geotechnical properties of ore‑related soil samples, including grain‑size distribution, particle‑size percentiles, plasticity indices, and specific gravity. The material is characterized through standard size‑fraction analysis (gravel, sand, silt, clay, and fines content), complemented by key percentile metrics (d10–d90) used to derive uniformity and curvature coefficients. Atterberg limits (LL, PL, PI) provide additional insight into the plastic behavior of the fine fraction. Each sample is classified according to the Unified Soil Classification System (USCS). Together, these parameters enable a comprehensive evaluation of the gradation, plasticity, and physical characteristics of the soils associated with ore extraction, supporting geotechnical interpretation and comparison among sample types. Funding This research was funded by the Ministry for Ecological Transition and Demographic Challenges (MITECO), Dirección General de Biodiversidad; TD by PRTR Medida C04.I03 belonging to “Asesoramiento en actuaciones de restauración de zonas mineras en el entorno del Mar Menor” Project (J. Butlanska) and “Estudio de las materias primas críticas y estratégicas para la transición ecológica y el suministro de las principales cadenas de valor industrial en España” Project (A.O. Oliva-González), and by grant PID2022-138197OB-I00 funded by MICIU/AEI/10.13039/501100011033 and by “ERDF/E” (R.L. Rodriguez-Pacheco).