At its discharge end the drum 9 has a delivery opening 56 of smaller diameter than the drum itself and has, projecting internally therefrom, adjacent this aperture and tangential thereto, opposed boxes 57 for lifting the stone/ sand water slurry at this discharge end through the opening 56. Each of the lifting boxes 57 is constituted by a length of angled metal with a web 58 across its inner end.Secured to the drum 9 and coaxial with the latter at its discharge end are three concentric perforated screens 59, 6t? and 61 of different diameters. The screens 59,canada gold mining machines price 60 and 61 are conically tapered outwards and are formed with a multiplicity of perforations of a size decreasing from those of the inner screen 59 to those of the outer screen 61. The screens are also of different lengths such that screen 59 terminates at its outer open end a greater distance from the drum 9 than the screen 60 and the latter in turn being of greater axial length than the screen 61.
The mouths of the screens each communicates with a separate chute which is directed so as to deliver the stones received from the respective screen to a separate point at the rear end of the machine. Hence, the mouth of the inner and longer screen 59 discharges into an open-topped, tapered, hopper-like casing 62 arranged at the rear of the machine and having a centrally and rearwardly directed delivery chute 63, the intermediate screen 60 delivers its stones into a hopper casing 64 arranged in front of casing 62 and having at its lower end an inclined delivery chute 65 which directs the stones from the mouth of screen 60 to one side of the centre line of the machine (see FIGURE 5) whilst a similar and larger hopper casing 66 is arranged in front of casing 64 to take the stones delivered from the mouth of outer screen 61, this further hopper having a discharge chute 67 directed towards the opposite side of the centre line from the chute 65.