cradle

mining tool

Also known as: rocker

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Last updated

June 25, 2026

Quick Summary

mining rocker The rocker, or cradle, which enabled one miner to handle more material than by simple panning. It was easy to transport and set up anywhere a source of water was available. The miner would shovel material into the hopper, regularly add water, and rock the cradle from side to side in order to sift the material onto the apron below. As the material was washed along, heavier minerals, especially gold, would be impeded by wood or metal riffles and collected by hand.

The term "cradle" has multiple meanings, and it's important to distinguish between them.

Cradle as a Harvesting Tool

In agriculture, a cradle is a rakelike implement used for gathering grain stalks after they have been cut by a sickle. A later European invention attached fingerlike prongs to a long-handled scythe, allowing it to cut and bundle grain simultaneously. This type of cradle is still used in some parts of the world.1

Cradle in Mining

In placer mining, a cradle (also known as a rocker) is a device used to separate valuable minerals, like gold, from ore. It resembles a child's cradle and is rocked back and forth with water and gravel. As it's rocked, the lighter material is washed away, while the heavier minerals, such as gold, are caught on riffles within the cradle. This method takes advantage of the high density of gold. Other placer mining techniques include panning and sluicing.2345

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placer mining
…pan was the rocker, or cradle, named for its resemblance to a child’s cradle. As it was rocked, it sifted large quantities of ore. Gravel was shoveled onto a perforated iron plate, and water was poured over it, causing finer material to drop through the perforations and onto an apron…
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…pan was the rocker, or cradle, named for its resemblance to a child’s cradle. As it was rocked, it sifted large quantities of ore. Gravel was shoveled onto a perforated iron plate, and water was poured over it, causing finer material to drop through the perforations and onto an apron…
Read More