An assaying vessel (2) and a method utilising the assaying vessel (2). The vessel (2) is during analyses of a free flowing non-liquid material. A sample (15) of the material is brought into the vessel (2), which comprises an analytical opening or slit (10) arranged in an enveloping wall (8) section having an inner side (17) facing downwards. A surface (5) area of the sample (15) is analysed through said opening or slit (10) by an analytical unit placed thereabove. The assaying vessel (2) also comprises means (18) for feeding or removal of the sample (15).
