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Gold Claims For Sale in BC

Kinds of Placer Deposits

A placer deposit or placer is a deposit that formed in moving water where particles/pieces of gold and/or other dense minerals have accumulated because the water flow isn't sufficient to keep them moving.

In many cases, for a placer deposit to accumulate gold over time, the water must be moving fast enough to flush out lighter sand. One aspect is that if a piece of sand and a piece of gold have the same weight, the piece of sand is much larger and is, therefore, pushed much harder by the flowing water.

The Ice Age and the word "Ancient"

When describing placer deposits, "Ancient" means either... For more information, see... Ice Age on the Glossary page.

Streams, Gulch and Fan Placer Deposits

Streams

Placer deposits in streams are found where...

A "slower part of the stream" includes the classic placer targets...

New sediment may create or add to gravel bars and stream bank deposits.

Gulches

A gulch is a narrow, steep-sided, steep valley. A gulch can carry large amounts of water and sediment during a flood caused by unusually rapid snow-melt or heavy rainfall.

In the Cariboo, Gulches with recent placer deposits - laid down since the last glacial period ended 11,000 years ago - were easy to find and mine, and were mostly depleted during the 1800s.

Ancient Gulch placer deposits can have thick overburden, although in some places it has been at least partially removed by recent streams,

Stevens Gulch and Beggs Gulch on Antler Creek host ancient gulch placers deposits.

Alluvial Fans and Fan Deltas

An alluvial fan is a fan or cone-shaped deposit of sediment that forms where a stream flows onto a flatter area. The water slows and drops much of its load.

At the Ballarat mine near Barkerville, gold-bearing alluvial fan deposits overlie (and are therefore younger than) the deeper pay gravels (described below).

Bench Placer Deposits

A bench is a flat area above a stream. It is what remains after stream down-cutting and lateral (sideways) erosion has removed part of what used to be the valley bottom or floodplain.

Old channels and old placer deposits can be buried on benches. Large bench deposits are a primary target for machine-digging operations. Small, buried benches in favorable locations can host small but rich placer deposits that are targets for hand-mining operations.

Ancient Channel Placer Deposits

Most ancient channels are deeply buried. Some placer mines are/were located where more recent erosion has removed some of the overburden.

Some types of ancient channels include...


Most examples and some of the material on this page came from:
Stratigraphy And Geologic Setting of Gold Placers in the Cariboo Mining District