Introduction
1. Overview of Physical Geology
2. Rock Identification Methods
Geologic Principles
3.

Maps & Navigation
Geologic Maps
4. Igneous Rocks
Magmatic Deposits
5. Plutonic-Related Deposits
Air Photos
6. Volcanic Rocks
Volcanic-Related Deposits
7. Sedimentary Rocks
Low Temp. Deposits
GPS Navigation
8. Hydrothermal Veins&
Alteration
9. Metamorphic Rocks
Metamorphic Deposits
10.

Structural Geology
Structural Controls on
Mineralization
** Mid Term
11. Mechanical Erosion
Placer Deposits
12. Geochemical Sampling Methods
13. Adit/Trench Mapping
Geochemical Methods
14. Geophysical Methods
15. Project Planning
Claim Staking
16. Exploration Drilling
Methods
** Final Exam

 

Class 11 Panning Lab

Objective:  Concentrate heavy minerals by using a gold pan.

Materials:  Borrow or purchase the following - Gold pan, grizzly, wash tub (or puddle), water, sand/gravel, BB’s or lead shot (or real gold flakes if possible).

Procedure:

  1. Place the grizzly above the gold pan and fill to about _ full with sand/gravel.  Add the lead shot or gold flakes. 
  2. Fill the tub about half full with water.  Submerge the grizzly and gold pan containing the materials to be panned. Be careful not to inadvertently let material wash over the side of the pan or grizzly.
  3. While submerged, vigorously shake the grizzly side to side to screen out the coarse material.  Discard the coarse material.
  4. Keeping pan submerged with about an inch of water above the gravel, begin to shake the pan side to side fairly vigorously.  It is important to keep the pan horizontal during this process.  Do not let material wash over the edge of the pan during this process.  Continue for several minutes.
  5. Lift the pan out of the water, keeping about an inch of water in the pan.  Gently tilt the pan forward, and with a slight rocking motion, allow the water in the pan to wash a few tablespoons of material out the front edge of the pan. Submerge the pan to get another inch of water on top of the gravel, and repeat the washing motion.  Repeat this washing method 6 ­ 8 times.
  6. Submerge the pan again to a depth of about one inch.  Again, shake the pan side to side vigorously, keeping the pan flat.  This allows the heavy minerals to migrate to the bottom of the pan.  The key is having the material completely submerged, as this is the only way the heavy minerals will be able to migrate downward.
  7. Again, lift the pan out of the water and repeat step 5.
  8. Again, submerge the pan and repeat step 4.
  9. When about 2/3 of the material has been washed from the pan using the method in step 5, submerge the pan and begin to use circular movements while gently tipping the pan forward.  Tip the pan forward just enough to allow small amounts of the upper layer of material to wash over the front edge of the pan.  When the pan is tilted, heavy mineralsmigrate to the corner of the pan, which is the objective. 
  10. After a few minutes using the technique of step 9, repeat step 6.  After a minute, repeat step 9.
  11. Continue alternating the techniques of steps 6 and 9 until about ý cup of material remains.  Lift the pan from the water after using the step 9 technique, allowing about ý cup of water to remain in the pan.
  12. Slowly and carefully swirl the water in bottom of the pan in a circular motion.  The light minerals will be winnowed sideways following the movement of the water.  The heavy minerals (lead shot or gold flakes) will lag behind.

Browse the information and images contained in the following web sites:

Placer Deposit Websites:

http://home.earthlink.net/~khinrichs/MRoberts.htm
Panning method summarized and other useful information.

http://imcg.wr.usgs.gov/panning/
Gold panning information ­ Chugach National Forest

http://www.goldgold.com/49erfiles/49pan_inst.htm
Simplified gold panning technique.