Home /Black Sand, What Is It? Gold, What Is It?  Selling Your Gold  Why Learn To Use A Gold Pan?


SO, JUST WHAT IS BLACK SAND?

 

I'll bet that unless you have been exposed to gold prospecting, you have never heard of "black sand".  What is it?  Well, of course, it is sand that is colored black. Anyone who has been a gold prospector or knows someone who is, also knows that black sand is the one thing placer prospectors are the most concerned with, other than heavy metals such as gold.

All throughout placer mining history, from the great Egyptians, to the Spanish in South America and the Forty Niners, gold prospectors have had a love hate relationship with black sand.  They look for it, and once they find it, do everything possible 

 

to remove it from the heavy metals they know are associated with it. Some black sands separate reasonably easily from the heavier metals, and some do not. So, if this sand is all black sand, what is the difference?
 

In case you are wondering, that's gold at the top of the picture, and black sand trailing down from it toward the bottom.

 

Placer mining, as a first step in understanding black sand, is no mystery, but simple science. It involves specific gravity. "Specific gravity", you say. "What is specific gravity, and what does it have to do with black sand?" Well, they go hand in hand and one cannot be removed from the other if you are to find gold. Specific gravity is the wet weight relationship of everything to water, with water being zero. Everything, once wet and under water, has a different weight than it does in the air. This weight relationship with water we call specific gravity.

Placer mining depends on this relationship to separate lighter materials from heavier ones. Black sand is one of the materials that is heavier and in abundance, so a prospector for gold looks for the abundant black sand knowing that heavier metals will also run along with it in rivers and streams. Oh, rivers and streams are the "water" part of separating black sand from lighter and heavier materials. Specific gravity helps us with the separation process by classifying the different sands and gravels in rivers and streams making it easier to find the black sand bands that are associated with gold and other heavy metals.

 

Black sand has a specific gravity of from 5 to 11, or 5 to 11 times the weight of water, depending on what is in the black sand. Gold, on the other hand, has a specific gravity of around 19 and platinum around 21. As you can see, gold and platinum can be two to three times the specific gravity of black sand, so you now understand how you would want to find black sand in order to find gold and other heavy metals.

"But what is in the black sand?", you ask, and so we return to our original question, "Black Sand, What Is It?"   It contains many heavy materials including hematite, magnatite (which, by the way, can be magnetic, but gets it's name from the area it was originally found in  called Magnesia, bordering

the ancient district of Macedonia), iron, iron pyrite, silvanites, lead carbonates, sphalerite, chromite, and sheelite, to name the most common. There are many combinations of these as well as many others in small amounts specific to an area and too numerous to list. Suffice it to say, they are all black or grey in color and so are known collectively as black sand.

Finding black sand is usually essential in finding heavier minerals and gemstones when placer mining, which are not as readily seen as black sand.  So, the next time you see that line of black sand along the shore of a river, lake, stream or ocean, you have a better idea of what it is..... and also what might be found along with it. Then, maybe, you can spend time being frustrated, like the rest of us, with finding ways to separate black sand from the more valuable minerals and gemstones often associated with it.
 

Copyright 2006-2012

All Rights Reserved  Shirley Weilnau and Hooked on Gold

 

HOME   Also Read Gold, What Is It?   SELLING YOUR GOLD  

Why Learn To Use A Gold Pan?

 

Please be advised that some of the ads shown on these pages may use tracking cookies or other methods of tracking.  You can disable this from your computer, but some pages may not show properly if you do.  You can also delete the temporary files and cookies from your computer on a regular basis.