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How to Dig or Pan for Semi Precious Stones in Iowa

Most semi-precious stones can be found in Iowa by digging or looking at the ground. Fresh water pearls are found along the Mississippi River. The pearls are found in the sand along the river bank or by harvesting mussels. Semi-precious stones found most commonly throughout Iowa include fossil coral, agate, moss agate, quartz, flint, onyx and geodes. Panning for semi-precious stones washes the dirt from the surface so the stone is more recognizable. Use the same process for semi-precious stone panning as used for gold panning.

Things You'll Need

12-inch to 14-inch plastic pans with riffles
12-inch to 14-inch sieve pan
Hand trowel or small spade
Bucket
Tweezers
Clear container with lid
12-inch square wire sieve
Squeeze bottle with water

Instructions

Panning
- 1
  Locate an area where the creek, stream or river is running over bedrock, which is composed of crystalline rocks.
- 2
  Find a location where the water is moving slowly, and dig into the ground 4 to 6 inches.
- 3
  Place the sieve inside a plastic pan with riffles. Place a large scoop of sand and rocks into the sieve.
- 4
  Place the plastic pan and sieve in the water so the water just trickles over the top of the pan. Fill the plastic pan with enough water to cover the sand by 1/2 inch.
- 5
  Tilt the pan at a 25- to 30-degree angle. Use a swirling motion, and swirl the water over the top of the sand. Periodically look at the larger rocks to check for semi-precious stones. Place the semi-precious stones in a container with a lid.
- 6
  Remove large rocks that are not semi-precious stones. Continue to swirl the pan until the last large rocks remain and semi-precious stones are removed. Lift the sieve from the plastic pan. Remove the remaining rocks from the sieve.
- 7
  Look carefully at the fine sand in the plastic pan. Check for semi-precious and precious stones. Remove any small semi-precious or precious stones with tweezers, and place them in a container with a lid.
- 8
  Submerge the plastic pan into the water so the running water trickles over the top edge. Add 1/4 inch of water over the top of the fine sand.
- 9
  Use a swirling motion with the pan tipped at a 25- to 30-degree angle. Check the sand periodically for semi-precious and precious stones. Continue swirling the water until the sand shows no signs of semi-precious stones.
Digging
- 10
  Locate an area of sand or gravel such as a sand pit.
- 11
  Dig into the ground with a spade, and fill the 12-inch square sieve.
- 12
  Shake the sieve with a back-and-forth or side-to-side motion. Look for semi-precious stones as the smaller stones fall through the sieve.
- 13
  Use a water bottle to squeeze water over the possible semi-precious stones so the surface is easily seen. Identify semi-precious stones.

Rocks & Minerals