With a name like montmorillonite, some might imagine that this curious, green clay originated on some distant, alien world, although Superman can be assured that the green hue does not mean it is anything to do with Kryptonite.
In fact, montmorillonite is the name given to a group of clays that swell in water, due to their chemical structure, with the green variety also being known as halloysite. Formed in volcanoes or hydrothermal outlets, they are made up of tiny particles of hydrous aluminium silicates.
These qualities mean that the substance is used as bleaching agents in some food production processes, such as making water and juices clearer and de-colouring vegetable oils.
However, the benefits for food and nutrition do not stop there. In its green clay form it can help cats and dogs as a detoxofier, binding with otherwise harmful agents.
Therefore, if you see an animal eating dirt, this is why they are doing it; to consume a substance that will help prevent various poisons from doing their worst. Indeed, while clays of various kinds contain important minerals, this in the primary benefit and why it can be beneficial for the health of your pets to mix some into their food.
However, it is also known to be good for humans. It has often been used in traditional medicine as a substance applied to open wounds as well as for dealing with stomach upsets, and in its calcium montmorillonite form it is known to aid the production of enzymes.
All that might make this slightly green substance a little bit less exciting that Kryptonite, but while it might not stop the man of steel flying around (assuming he can actually find a phone box to change in these days), it will certainly have that effect on a few nasty bugs that could otherwise trouble people or their pets.