  The discovery of extremely zirconium- and lead-rich surfaces amongst a small
subgroup of hot subdwarfs has provoked questions pertaining to chemical
peculiarity in hot star atmospheres and about their evolutionary origin. With
only three known in 2014, a limited search for additional `heavy-metal'
subdwarfs was initiated with the Subaru telescope. Five hot subdwarfs having
intermediate to high surface enrichment of helium were observed at
high-resolution and analyzed for surface properties and abundances. This paper
reports the analyses of four of these stars. PG1559+048 and FBS 1749+373,
having only intermediate helium enrichment, show strong lines of triply ionized
lead. PG1559+048 also shows a strong overabundance of germanium and yttrium.
With more helium-rich surfaces, Ton 414 and J17554+5012, do not show evidence
of heavy-metal enrichment. This limited survey suggests that extreme enrichment
of `heavy metals' by selective radiative levitation in hot subdwarf atmospheres
is suppressed if the star is too helium-rich.
