Aims. We report the detection of an unusually high lithium content in HD 232862, a field giant classified as a G8II star, and hosting a magnetic field. Methods. With the spectropolarimeters ESPaDOnS at CFHT and NARVAL at TBL, we collected high resolution and high signal-to-noise spectra of three giants: HD 232862, KU Peg and HD 21018. From spectral synthesis we inferred stellar parameters and measured lithium abundances that we compared to predictions from evolutionary models. We also analysed Stokes V signatures, looking for a magnetic field on these giants. Results. HD 232862, presents a very high abundance of lithium (ALi=2.450.25dex), far in excess of the theoretically value expected at this spectral type and for this luminosity class (i.e.,G8II). The evolutionary stage of HD 232862 was determined, and it suggests a mass in the lower part of the [1.0M, 3.5M] mass interval, likely 1.5-2.0M, at the bottom of the red giant branch. Also, a time variable Stokes V signature was detected in the data of HD 232862 and KU Peg, pointing to the presence of a magnetic field at the surface of these two rapidly rotating active stars. Key words: stars: abundances - stars: evolution - stars: magneticfields - stars: individual: HD 232862 - stars: individual: KUPeg
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