Superconducting receive coils can be used to improve the signal to noise ratio of a MRI system. The greatest improvement is seen in cases where it is the coil noise dominates the noise. This is the case for low field MRI where surface coils are used. The properties of large area (100 mm square) YBCO thick film coils designed for a compact very low field MRI system are reported. The properties are compared with copper and silver mimics.