delta76 dutchy101 never seen one. I believe stone is a no -no for specialty coffee. i.e. if a stone is found the batch will be disqualified as specialty
delta76 MWJB right, I remember it incorrectly. One large stone or up to 4 medium stones per 300gr is “acceptable” Annex 7: Green Coffee Classification and Grading (fao.org)
Dusk It must surely be almost impossible to remove the chance of any stones and surely speciality coffee is likely to come from smaller producers and through smaller processing plants that might not have the capabilities of big producers (for example Illy or Lavazza).