Buried and Auriferous Placers

Alluvial, eluvial, aeolian and beach placers might get buried after they have formed and are at times referred to as buried placers. These placers can become buried in a variety of different areas such as:

• In volcanic deposits like the ones that can be found in the areas of Australia and California.
• In glacial deposits like the ones that can be found in the areas of Canada and Russia. 
• In talus as well as other slope deposits
• In aeolian deposits like the ones that can be found in the areas of Australia.
• In alluvial gravels and sands. 
• In marine and lacustrine deposits.

The gold in auriferous placers might come from one or more of the subsequent resources:

• Auriferous quartz veins and other kinds of deposits that are gold bearing. 
• Auriferous sulphide impregnation areas and porphyry copper deposits.
• Auriferous poly-metallic deposits.
• In somewhat auriferous quartz stringer, blows, veins in schists, and gneisses as well as several other types of rocks.
• A range of somewhat auriferous minerals such as pyrite and other sulphides in graphitic schists and other rocks.
• In somewhat auriferous conglomerates, quartzites as well as other rocks.
• Ancient placers. 

Something that should be pointed out is that the geological records of productive placers is in most cases multifaceted, a lot more than the cycle which consists of:

• Main vein or lode source.
• Eluvial gold placer.
• Alluvial gold placer.

In many cases a transitional collector of gold is drawn in primarily auriferous conglomerates, quartzites, etc. An amount of alternatives can be seen in the lode placer succession in this way:

• Lode, deluvial placer, interceptor, alluvial placer
• Lode, interceptor, alluvial placer.
• Interceptor, alluvial placer.

The most important agent that brings about the different kinds of gold placers is directly related to weathering and this is a development that entails a great number of intricate chemical reactions. There are a few different things that can occur to gold when in primary deposits which are:

• The gangue minerals might have crushed up and slipped away, leaving the gold fairly untouched.
• The gold might have stayed in situ in the oxidized zones or might have gone into eluvial and alluvial placers.
• The gold might have gotten dissolved and been taken a good distance away from the deposits in which case no placers are formed.

The gold that has dissolved may perhaps be entirely or moderately re-precipitated on nuclei of gold in the residuum or on comparable nuclei as they are stirred down in the alluvium of rivers, streams, beaches and so forth. The last procedure is what usually produces gold nuggets