" Jansari said there was a misguided impression that the British Museum did not know -- or care -- about how artefacts entered its collections, whereas a lot of people were actually researching the provenance of items.
"These companies are under pressure to show world beating growth in volumes and the provenance of these statistics is unclear at best," she says.
" Researching a picture's provenance is crucial, says Mr Di Petta, but he admits to accidentally posting fakes.
