Patent ID: 7012209

Claim:
A method of collecting minus 20 mesh gold using a sluice including a gold collecting medium, comprising: using water having a PH range between 4 and 8; flowing the water over the gold collecting medium in a to induce a positive surface charge on the gold collecting medium due to the interaction between the water and the gold collecting medium; feeding minus 20 mesh gold laden material into the sluice with the flowing water to induce a negative surface charge on minus 20 mesh gold particles of the colloidal gold laden material and create a slurry of minus 20 mesh gold laden material and water, whereby the water induces a negative surface charge on the minus 20 mesh gold particles; setting the flow rate of the slurry into the sluice such that the minus 20 mesh gold particles are attracted to the gold collecting medium; and collecting the minus 20 mesh gold particles from the gold collecting medium that were attracted to gold collecting medium.