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Rare high-³He/⁴He signatures in ocean island basalts (OIB) erupted at volcanic hotspots derive from deep-seated domains preserved in Earth’s interior. Only high-³He/⁴He OIB exhibit anomalous¹⁸²W—an isotopic signature inherited during the earliest history of Earth—supporting an ancient origin of high³He/⁴He. However, it is not understood why some OIB host anomalous¹⁸²W while others do not. We provide geochemical data for the highest-³He/⁴He lavas from Iceland (up to 42.9 times atmospheric) with anomalous¹⁸²W and examine how Sr-Nd-Hf-Pb isotopic variations—useful for tracing subducted, recycled crust—relate to high³He/⁴He and anomalous¹⁸²W. These data, together with data on global OIB, show that the highest-³He/⁴He and the largest-magnitude¹⁸²W anomalies are found only in geochemically depleted mantle domains—with high¹⁴³Nd/¹⁴⁴Nd and low²⁰⁶Pb/²⁰⁴Pb—lacking strong signatures of recycled materials. In contrast, OIB with the strongest signatures associated with recycled materials have low³He/⁴He and lack anomalous¹⁸²W. These observations provide important clues regarding the survival of the ancient He and W signatures in Earth’s mantle. We show that high-³He/⁴He mantle domains with anomalous¹⁸²W have low W and⁴He concentrations compared to recycled materials and are therefore highly susceptible to being overprinted with low³He/⁴He and normal (not anomalous)¹⁸²W characteristic of subducted crust. Thus, high³He/⁴He and anomalous¹⁸²W are preserved exclusively in mantle domains least modified by recycled crust. This model places the long-term preservation of ancient high³He/⁴He and anomalous¹⁸²W in the geodynamic context of crustal subduction and recycling and informs on survival of other early-formed heterogeneities in Earth’s interior.