List of minerals tested

This is a list of minerals that have been tested for semiconducting properties through the course of this research. The list is based on more in availability on Cornish mine sites rather than the types commonly used for semiconductors. Some minerals commonly used such as carborundum and zincite are extremely rare in this location, or in nature (carborundum can be found in some meteorites).

All the photos in these pages are taken of specimens I've found in Cornish mine waste. Often they are not the same specimen as the curve traces - as a rock that is good to photograph is often different to one that is amenable to electronic experiments! The curve plots themselves are chosen to be more representative than 'best case' as they all vary quite a lot depending on the particular specimen and point contact location.

• Pyrite
• Galena
• Chalcopyrite
• Chalcocite
• Arsenopyrite
• Cassiterite
• Löllingite
• Cuprite
• Wolframite (resistance too high)
• Molybdenite
• Hematite
• Native copper (+cuprite resistance too low)
• Marcasite

To test

• Bournonite
• Anatase
• Tetrahedrite

To find

• Magnetite
• Stannite