Although Thermite originated in the late 1800’s I believe inventive/imaginative prospectors can employ this somewhat ancient technology today, because it is an easy method of getting metal-in-hand.

Before proceeding I must state that microscopes are one of my best friends, whereas the Vreeland spectroscope/spectrograph is an indispensible Partner.

The objective of this www page is to illustrate and describe how easy it is to utilize thermite to generate an exothermic reaction that liberates metal from the oxide, which in this case is Iron, but could just as easily be copper, silver, etc., including black sands.
Note: Not all black sands are oxides.

Contained in the bowel is a commercially purchased 325 mesh Red Iron Oxide (Fe2O3), with a purity of 99%. Higher purities are expensive.
Normally, I grind a mineral oxide in a ceramic mortar then screen it to -150 mesh.
The finer the grind the better the results.

10x – a magnified view of what 325 mesh red iron oxide looks like

20x – A magnified view of the preceding image.

A small amount of the Iron Oxide placed upon a graphite pad that is resting upon a ceramic hearth/crucible. This iron oxide will be subjected to the high heat of the Vreeland Spectroscope’s electric arc to yield spectral lines thereby determining what this oxide contains.

The completed Vreeland Spectroscope burn produced this metallic bead.

8x – a magnified view of the preceding image.
The contaminating elements detected with the Vreeland spectroscope in this Iron Oxide were:
Sr = fair, Ca = fair, Mg = fair, Gd = faint, Pt = fair (1 major line of 3) & Ru = very faint.

The copper coated Carbon Electrodes that have been used need to be cleaned.

The carbon arc electrodes are cleaned prior to being used for each of the following spectroscopic burns to avoid potential contamination.

Inexpensive, commercially purchased 425 mesh Aluminum Powder with a purity of purity of 99.7%.
I have found -325 mesh to also be just as effective as this 425 mesh aluminum powder.

20x – A magnified view of preceding image.

The aluminum powder is on a graphite pad that rests upon a ceramic crucible and is ready for a burn on the Vreeland Spectroscope to determine what kind of impurities may be present.

The completed spectroscopic burn of the aluminum powder.

8x – a magnified view of the preceding image.
The only impurities of this aluminum powder detected with the Vreeland Spectroscope were: Ba = faint, Sr = faint to fair, Ca = fair, La = very faint, Cd = very faint.

Knowing what the impurities are before ignition of the thermite allows me to know what the molten iron (or any oxide) did or did not collect during the fusion process.

The thermite mixture is in a papier-mâché container and there is a Magnesium metal ribbon which is the fuse that ignites the thermite. A hand held propane torch flame is used to ignite the Magnesium metal ribbon. I have found that making different sized papier-mâché containers is the only practical way of containing the high heat and resultant molten metal.
I wear goggles to protect my eyes prior to igniting the Magnesium Ribbon and during the thermite fusion.
When watching the video notice how molten metal is ejected.


Watch Video


The solidified molten mass is resting in the hole dug into the firebrick and the papier-mâché container has almost burnt to ashes.

The papier-mâché container has burnt up and blown away allowing this picture to be taken of the still very hot mass. It often takes 30 minutes before this fused mass can be safely handled and removed from the firebrick. I have found firebrick to be the best medium to contain molten metal.

The slag and attached metal button have been removed from the hole dug-out of the firebrick. The purpose of the hole in the firebrick is to allow the metal to accumulate, whereas without this hole the molten metal has a tendency to explode and be thrown in a 360 degree circle making retrieval very difficult.

One side of the fused mass.

The opposite side of the fused mass exposing the metal button.
Weight of metallic melt mass (slag and metal) = 32 grams

Weight of the retrieved metal button = 11 grams, that was removed from the pocket of the glassy slag which is full of metal shot.

The metal button has been broken open revealing the crystalline internal structure of metal, which can also provide clues as to what may be contained within the metal matrix.

8x – A low magnification of the internal appearance of the broken metal button.

Some of what appears to be slag, but is full of metal shot as seen in the next two images.

8x – solidified metal beads are ever-where in the glassy slag metallic matrix. What appears to be slag is actually a high percentage of metal, but would require a very fine grand to liberate and capture.

8x – another low magnification view of the numerous metal beads in the slag, which can be retrieved by grinding in a ceramic mortar.

The retrieved metal can be subjected to a variety of chemical tests, such as dilute or concentrated HCl or HNO3.
Once the iron is dissolved any gold ought to be a very fine blackish powder that when annealed should become the color of gold. If other metals are present that won’t dissolve in hydrochloric or nitric acids they too will be various sized powders that can be filtered and examined.

I have only scratched the surface of what thermite might allow me to accomplish.
I am still learning with each thermite fusion about the many varied minerals, as well as how to mix known's with unknowns thereby collecting like mercury collects gold the different elements that may be present in what may look like simple limonite.
My view of prospecting is try to not allow my desire to find precious metals to blind my eyes to other potential ore possibilities.
Opportunity is always present if a prospector will just be creative enough to LOOK.


Created: 04-13-2011
Last edited:: 08-11-2011

Send email regarding questions and/or comments to:
Joseph Cummins