In Piacenza, they are better known as sbrislon or grasei.
They are the residues of meat and cartilage from the processing of cured meats and sausages in general, mainly consisting of by-products of the processing of pork and even goose.
They appear as irregular pieces of hazelnut flesh more or less dark, depending on whether the fusion took place thoroughly and at high temperature.
Rich in residual fat and tasty, greaves are widely used in regional cuisines.