Per-element reference properties for magnet-candidate screening: physical constants, crustal/solar abundance, HHI supply-risk indices (production + reserves; Gaultois et al. Chem. Mater. 2013 — the same table behind the hhi_score column in magnet_dataset_clean, weight-fraction-weighted), and elemental cost. Cost columns: cost_partner_usd_per_100g (partner-provided vintage) and cost_2013_usd_per_100g (pymatgen cost DB, Wolfram/Wikipedia Sept 2013 — stale, kept for reference). Toxicity and environmental-impact columns pending source selection (candidates: PubChem GHS hazard codes, NIOSH/OSHA exposure limits, Nuss & Eckelman 2014 cradle-to-gate GWP/CED).

Per-element reference properties for magnet-candidate screening: physical constants, crustal/solar abundance, HHI supply-risk indices (production + reserves; Gaultois et al. Chem. Mater. 2013 — the same table behind the hhi_score column in magnet_dataset_clean, weight-fraction-weighted), and elemental cost. Cost columns: cost_partner_usd_per_100g (partner-provided vintage) and cost_2013_usd_per_100g (pymatgen cost DB, Wolfram/Wikipedia Sept 2013 — stale, kept for reference). Toxicity and environmental-impact columns pending source selection (candidates: PubChem GHS hazard codes, NIOSH/OSHA exposure limits, Nuss & Eckelman 2014 cradle-to-gate GWP/CED).