Zirconium rhymes with:
ammonium, gonium, harmonium, pandemonium, plutonium, polonium, ammonium, capernaum, condominium, cranium, didinium, geranium, gonium, hafnium, harmonium, millennium, minium, neptunium, pandemonium, plutonium, polonium, selenium, titanium, uranium
Zirconium sounds like:
zarcone, zercomo, zircon, zorkin