People living in parts of Staffordshire have been asked to look out for "dark shiny rocks that stand out" after a meteorite was suspected to have landed in the county.
A bright fireball seen over the Midlands in the early hours of 6 May may have dropped a meteorite somewhere around Blythe Bridge and Uttoxeter, according to the UK Fireball Alliance (UKFAll).
People were asked by scientists not to touch it with their bare hands if they found it.
Teams of researchers from several universities have already searched fields around Blythe Bridge and Uttoxeter but were yet to make a discovery.
UKFAll estimated 500g (1.1lbs) of meteorite landed south-east of Stoke-on-Trent and would be about 5-10cm (2-4inches) wide, black or brown in colour and might have a glassy outer surface.
Dr Ashley King hoped someone living or working in the area might find the rock but asked people to be respectful while searching.
“We don’t want anyone taking risks looking for it or going into areas where you shouldn’t," he said.
Richard Baggaley is chairman of a greenhouse factory in Cresswell, a village in the middle of the search area.
Scientists from the University of Glasgow asked to look around his land in the days after the sighting, he said.
“They were very excited. We were just amazed that such a thing could happen in our little corner of Staffordshire," Mr Baggaley said.
Listen on BBC Sounds: Greenhouse People chairman Richard Baggaley said he was relieved the meteorite had missed his factory
Anyone who suspected they have found the meteorite were asked to contact UKFAll or the Natural History Museum.
A spokesperson for UKFAll said people should not touch the rock with their bare hands to avoid contamination.
They suggested picking it up in aluminium foil or a clean, dry sandwich bag.