We have fabricated single-phase samples and measured the bulk properties fo
r one (Er) of a series of ternary, heavy rare-earth, 221 ''plumbide'' inter
metallic compounds R2Ni2Pb (R = rare earths). These materials form in the o
rthorhombic (space group Cmmm) structure which is isostructural to Mn2AlB2
compounds. Our results of susceptibility, magnetization, heat capacity, and
(magneto) resistivity on Er2Ni2Pb show (sharp) multiple antiferromagnetic
transitions and strong field dependences in all bulk properties for the tem
perature range 2-10 K. We relate this magnetic behavior to the unusual R sy
mmetry (partially frustrated) of the highly anisotropic plumbide crystal st
ructure.