The complete build process for crystal power cells.
Solid magnesium rod. Aluminum can also be used but will give a lower voltage.
Copper pipe cap.
Equal Parts of the following:
Potassium chloride - commonly known as salt substitute.
Hydrated potassium aluminium sulfate - commonly known as alum.
Sodium tetraborate - commonly known as 20 mule team Borax.
Magnesium sulfate - commonly known as epsom salt.
Reliance 9001829005 32-Inch Magnesium Water Heater Anode Rod
Great prices on magnesium here: http://www.mcssl.com/store/gallium-source/magnesium-metal
Galvanic Chart: http://www.nordhavn.com/resources/tech/images/Galvanic_Series.pdf