| U.S. rare-earth concentrate output (REO) | 51,000 t and USD 240M | USGS MCS 2026 chapter, published 2026-02 | Shows domestic output scale but not full self-sufficiency for downstream NdFeB supply chains. | [S1] |
| U.S. imports of RE compounds/metals | +169% volume in 2025; value USD 165M vs USD 168M in 2024 | USGS MCS 2026 chapter, published 2026-02 | Procurement risk is driven by product mix and category shifts, not only by headline import value. | [S1] |
| World rare-earth production estimate | 390,000 t in 2025 | USGS MCS 2026 foreword (published 2026-02) | Global supply expanded, but growth does not remove concentration and policy-shock exposure. | [S3] |
| Heavy rare-earth net import reliance (U.S.) | 100% in 2025 (compounds and metals) | USGS MCS 2026 heavy rare earths chapter, published 2026-02 | High-temperature NdFeB lanes can inherit geopolitical and licensing risks through Dy/Tb exposure. | [S2] |
| Rare-earth demand change in STEPS | +50% to +60% by 2040 | IEA Global Critical Minerals Outlook 2025 | Even moderate scenario growth keeps pressure on magnet-material qualification and sourcing plans. | [S4] |
| China projected refining share (battery-grade graphite + rare earths) | Around 80% in 2035 | IEA Global Critical Minerals Outlook 2025 | Dual-lane sourcing should start before RFQ freeze for high-risk temperature classes. | [S4] |
| N-1 supply coverage for graphite + rare earths | Only 35% to 40% of N-1 demand in 2035 | IEA Global Critical Minerals Outlook 2025 | Single-country disruption can invalidate otherwise "balanced" supply assumptions. | [S4] |
| Salt spray as field-life predictor | Seldom correlates when used as stand-alone data | ASTM B117-26, last updated 2026-01-19 | Do not convert fog-test hours directly into service-life commitments without corroborating evidence. | [S10] |
| U.S. net import reliance (RE compounds/metals) | About 67% in 2025 (down from >90% in 2024) | USGS MCS 2026 Rare Earths chapter, published 2026-02 | Dependence improved versus 2024, but import exposure remains high enough to require dual-lane planning. | [S14] |
| U.S. apparent consumption (RE compounds/metals) | 27,000 t REO in 2025 vs 9,010 t in 2024 | USGS MCS 2026 Rare Earths chapter, published 2026-02 | Demand rebound can compress lead-time buffers if RFQ and validation gating are delayed. | [S14] |
| China share of U.S. RE imports by value | Average 71% (2021-2024) | USGS MCS 2026 Rare Earths chapter, published 2026-02 | Country concentration remains material for NdFeB programs even when domestic mine output increases. | [S14] |
| Rare-earth oxide price dispersion (2025, China market) | NdPr +25% ($55->69/kg), Tb +24% ($812->1,010/kg), Dy -7% ($257->239/kg) | USGS MCS 2026 Rare Earths + Heavy Rare Earths chapters | Do not treat heavy-RE exposure as one blended surcharge; element-specific terms are safer for contracts. | [S14][S15] |
| Chinese permanent-magnet exports | About 58,000 t in 2024 | IEA commentary on export controls, published 2025-12-04 | Short approval delays can rapidly affect downstream inventories when market dependence is high. | [S16] |
| EU strategic benchmark package (CRMA) | 2030 targets: 10% extraction, 40% processing, 25% recycling, <=65% single-country dependency | Regulation (EU) 2024/1252, effective 2024-05-23 | EU-facing RFQs should include origin traceability and recycling disclosure gates before final award. | [S12] |
| Air carriage magnetic-field limit (U.S.) | >0.00525 gauss at 4.5 m from any package surface is forbidden | FAA PackSafe page last updated 2023-03-15; eCFR current to 2026-03-19 | Technical fit alone does not guarantee ship readiness; package-field checks must be part of launch gating. | [S19] |
| U.S. consumer magnet hazard threshold | Hazard criteria include small-part fit plus flux index >=50 kG2 mm2; subject products must stay below 50 | 16 CFR part 1262 current text, accessed 2026-02-19 | Consumer-facing loose-magnet products need compliance screening before using catalog strength claims in go-to-market plans. | [S20] |
| U.S. high-powered magnet injury baseline | Estimated 26,600 emergency-department visits (2010-2021) and 7 reported deaths | 16 CFR part 1262 findings and CPSC final-rule release (2022) | If magnets can become loose parts, safety risk can dominate material-choice logic even when force targets are met. | [S20][S21] |
| Rare-earth demand vs secondary supply (2024, STEPS) | 91 kt demand vs 27 kt secondary supply (~30%, inferred) | IEA rare-earth data page, updated 2025-05-21 | Secondary supply helps but does not replace primary extraction and refining resilience planning. | [S22] |
| Top-three concentration (2024, STEPS) | Mining 86%; refining 97% | IEA rare-earth data page, updated 2025-05-21 | Supplier-count diversification can still mask concentration risk if upstream refining remains highly clustered. | [S22] |
| Finite-cylinder demag model coverage for disc geometry | Nf and Nm were calculated for 0.01 <= gamma <= 50 (2D model), with one-dimensional extension from gamma >= 10 | IEEE Transactions on Magnetics 27(4), published 1991-07 | Thin-disc aspect ratio shifts demagnetizing behavior enough to require geometry-aware checks before grade lock. | [S62] |
| Cylinder demag quick-approximation error band | Sato-Ishii approximation for uniformly magnetized cylinders reports <4.25% error for n < 100 (n = length/diameter) | Journal of Applied Physics publication date 1989-07-15 | Fast screening formulas are useful for disc RFQ triage, but teams must still validate assumptions with program-specific models. | [S63] |
| Axial-versus-transverse finite-cylinder formula availability | 3D Maxwell-based approximate formulas were reported for finite cylinders in axial and transverse fields | Physical Review Applied 10, published 2018-07-01 | Axial and diametral magnetization routes should not be treated as interchangeable without direction-specific checks. | [S64] |
| Disc-coating single-study benchmark (Zn-Fe with Cr(III)) | A 0.9 wt.% Fe passivated Zn-Fe coating endured 210 h neutral 3.5 wt.% NaCl spray without white rust (3-4x pure Zn) | Materials (MDPI) 15(21):7523, published 2022-10-27 | Coating stack decisions can materially shift disc durability, but one study is not enough for universal lifecycle claims. | [S65] |