AgResearch wants farmers to make contact if they see any lambs in their flock with a strange and wondrous fleece.
David Scobie from the institute's enhanced wool quality project team, said scientists are particularly interested in lambs with a lustrous or shinier fleece.
He said lustre mutant sheep grow wool similar to the English Leicester and Border Leicester breeds, or mohair from an Angora goat.
Dr Scobie said the fleeces which appear from time to time, are difficult to process because they tend to cott, but may help scientists understand why the average fleece felts during processing.
He said they're not very common at all.