Sluice box mouth and sifter pan system

1. A sluice box mouth, comprising:

an open input end;

an open output end opposing the input end;

a substantially planar bottom plate extending from the input end to the output end;

a first upright sidewall extending along a first edge of the bottom plate, the first upright sidewall having a first end portion proximate the output end, a second end portion proximate the input end, and a first arcuate portion between the first end portion and the second end portion; and

a second upright sidewall extending along a second edge of the bottom plate opposing the first edge, the second upright sidewall having a first end portion proximate the output end, a second end portion proximate the input end, and a second arcuate portion between the first end portion and the second end portion, wherein the first end portion of the first sidewall is parallel to the first end portion of the second sidewall, further wherein the second end portion of the first sidewall and the second end portion of the second sidewall are spaced at an acute angle from each other, thereby defining a progressively widening space therebetween.

2. The sluice box mouth according to claim 1 , wherein the vertex of the acute angle lies within the first and second end portions of the first and second sidewalls.

3. A sifter pan comprising:

a horizontal bottom support including a substantially horizontal base and a filtering mesh on the base, the base including a substantially hexagonal frame, a central opening within the frame, and a plurality of intersecting ribs extending from respective corners of the frame across the central opening;

a circular upper rim; and

a peripheral side wall extending between the bottom support and the upper rim, wherein an outer surface of the peripheral wall includes a substantially hexagonal collar and a circular upper ledge spaced from the hexagonal collar.

4. A sluice box system, comprising:

a sluice box and sluice box mouth system comprising:

the sluice box having a bottom plate and first and second upright sidewalls extending from opposing edges of the bottom plate;

the sluice box mouth having sidewalls, the sidewalls configured to have a sequential linear portion, an arcuate portion, and a flared portion, wherein the flared portions of the sidewalls define a progressively widening space therebetween, the linear portion of the sidewalls are parallel, the arcuate portions being disposed between the linear portions and the flared portions, and the bottom plate includes a grooved portion extending between the linear portions; and

at least one sifter pan, the at least one sifter pan comprising:

a first sifter pan, the first sifter pan including a horizontal bottom support, a circular upper rim, and a peripheral side wall extending between the bottom support and the upper rim, the horizontal bottom support including a base and a filtering mesh, the mesh being disposed on the base,

wherein the bottom plate is configured to removably receive the first sifter pan, and

wherein the arcuate portions of the first and second upright sidewalls are configured and dimensioned to engage the peripheral side wall of the sifter pan.

5. The sluice box system according to claim 4 , further comprising one or more additional sifter pans, the one or more additional sifter pans being stackable on the first sifter pan to provide a stacked configuration of sifter pans.

6. The sluice box system according to claim 5 , wherein each of the sifter pans each has a substantially hexagonal collar and a circular upper ledge extending from the peripheral wall, wherein the collar of one sifter pan is positioned upon the circular upper ledge of an adjacent sifter pan in the stacked configuration.

7. The sluice box system according to claim 4 , wherein the flared portion of the sidewalls, which define the progressively widening space, are spaced at an acute angle from each other.

8. The sluice box system according to claim 7 , wherein the vertex of the acute angle lies within the linear portions of the sidewalls.