  A polycrystalline sample of vesignieite BaCu3V2O8(OH)2 comprising a nearly
ideal kagome lattice composed of Cu2+ ions carrying spin 1/2 has been
synthesized and studied by magnetization and heat capacity measurements.
Magnetic susceptibility shows a neither long range order, a spin glass
transition nor a spin gap down to 2 K, in spite of a moderately strong
antiferromagnetic interaction of J/kB = 53 K between nearest-neighbor spins. A
broad peak observed at a temperature corresponding to 0.4J in intrinsic
magnetic susceptibility indicates a marked development of the short-range
order. The ground state of vesignieite is probably a gapless spin liquid or is
accompanied by a very small gap less than J/30.
