Point load test dataset for moisture-dependent brittleness and indentation indices of phyllite (Usfan, Saudi Arabia)

This dataset supports a study of two field indices extracted from a single point load test on phyllite: the Point Load Brittleness Index (PLBI) and the Point Load Pre-Failure Indentation Deformation index (PLP-FID). Thirty irregular phyllite lumps sampled near Usfan, western Saudi Arabia (21.923 N, 39.356 E), were conditioned to oven-dry, partially saturated, and fully saturated states (10 specimens each, between-specimen design) and tested under ASTM D5731. The archive contains: specimens.csv, the master specimen-level dataset (30 specimens, 48 variables covering physical properties, moisture state, point load measurements, sieve and fragmentation masses, and the derived indices); data_dictionary.csv describing every variable; and 18 derived result tables (descriptive statistics, effect sizes, Welch ANOVA and post-hoc tests, percentage reductions, classification bands, power analysis, correlations, and uncertainty budgets) that reproduce the figures and tables of the associated manuscript. Analysis scripts and a one-command reproducibility capsule are available from the corresponding author on reasonable request.