Placer Gold Recovery Methods by Michael Silva

[Steve Herschbach]

A decent summary of placer gold recovery methods with good illustrations. A good place to start for beginners so pinned here. 5mb pdf download, 29 pages with excellent references. The reference list on page 29 should be followed up on for more detailed information - Google is your friend.

https://www.conservation.ca.gov/cgs/Documents/Publications/Special-Publications/SP_087.pdf

CONTENTS

INTRODUCTION  1
CONCENTRATION OF PLACER GOLD ORE  2
SMALL SCALE RECOVERY EQUIPMENT  2
Gold Pan 2
Rocker  3
Construction  3
Assembly 5
Operation  5
Sluices  6
Long Tom  7
Dip-Box  8
Shaking Tables  8
Portable Processing Equipment  10
Amalgamation 10
DRY PLACERS  10
Dry Washers  10
Air Tables (Oliver Gravity Separator)  11
MODERN RECOVERY EQUIPMENT  12
Pinched Sluice Systems  12
Spiral Concentrators  13
Rotating Spirals  15
Helixes  15
Jigs  16
Fine Material Separators  20
Bartles-Mozely Separator  20
Bartles CrossBelt Separator  21
Centrifugal Concentrators  21
Bowls 21
Knelson Concentrator  22
SUMMARY  22
OPERATING MINES  23
Hammonton Dredge  23
Hansen Brothers - Hugh Fisher  25
Bear River  26
Greenhorn Creek  26
TRI-R Engineering - Stinson Mine  27
SELECTED ANNOTATED REFERENCES 29

While this publication does a good job summarizing everything from the gold pan to some pretty sophisticated recovery devices, the one thing missing completely is the gold suction dredge. For that, see my article below on that subject:

Suction Gold Dredge Basics

For a more in depth look at suction dredges, see Keene’s Suction Dredging - Understanding the Basics