"Artemus" wrote

It seems to me that water jets around the perimeter of the suction head
would work better than a vibrator. They would stir up the fines and leave
the bigger stuff on the bottom. A vibrator would cause the fines to
settle
even deeper. But I'm no expert on the matter.
Art

Underwater, you have to have an opposing jet for every jet you have to
cancel the force that jet makes in the opposite direction from the way it
blows. A large force of water at the head would be no problem using a T, as
we did underwater, then using hundreds of pounds of water pressure with no
resulting force in any direction.

Jets would aggravate a big area, so should be kept small, or it would just
blow all the stuff you want into the water around you. I'm thinking of
things that will keep all the action in a 2' cylindrical area. The object
is to penetrate deeper than just the surface, not to blow the gold all over
the place, and suck it up through smaller holes so that the amount of
material you actually pick up would be minimized. Most gold is less than 1"
anyway, and in that area, it's a lot smaller than that. Big nuggets are
rare in that area.

Steve