2001ApJ...553..405L

We utilize high-resolution, high signal-to-noise spectra to perform a differential analysis of Fe abundances in the common proper-motion pair 16 Cyg A and B. We confirm that both stars are slightly metal-rich compared to the Sun, and we show for the first time that the primary is enhanced in Fe relative to the secondary by a significant amount. We find Δ[Fe/H]=0.025±0.009. This tends to support a ``self-pollution'' scenario, though lack of a complete understanding of small primordial metallicity variations among binaries and open cluster members prevents a definitive conclusion.