12th January: Iron

In the French Revolutionary Calendar, today celebrates Iron. Some facts about the element iron:

1. Iron has an atomic number of 26 and its chemical symbol is Fe (from the Latin, ferrum).
2. It is the most common element on Earth and the sixth most abundant in the entire universe. It is created by fusion reactions in large stars. There are significant amounts of iron in the Sun.
3. Pure iron is a soft metal - the hardness of industrial iron and steel comes from impurities created by the smelting process, in particular, carbon.
4. Iron is necessary for life. It is present in the compounds haemoglobin and myoglobin which transport Oxygen in animals. Blood is red because of the iron in it, and human blood smells of it. Plants use it as part of the process of photosythesis. An average man has a total of around 3.8 g of iron in his body and the average woman about 2.3 g.
5. Sources of iron in the diet include red meat, Lentils, beans, poultry, fish, leaf vegetables, watercress, tofu and chickpeas. However, don't overdo it. In large amounts, iron can be extremely toxic. 20 milligrams of iron per kilogram of body weight is toxic, while 60 milligrams per kilogram is lethal.
6. Mars is red because the dust on its surface is rich in iron oxide.
7. There are Bacteria which eat iron. They are found in the hulls of sunken ships, including the Titanic. It’s estimated that within 50 years the hull and structure of the Titanic will collapse entirely because of the bacteria eating it. Nom nom nom.
8. There is a mountain in Russia, called Magnitogorsk that is made almost entirely of iron with an estimated 7-10 Billion pounds of Iron Ore. A city grew up around it, and much of it has now been mined.
9. In superstition, iron is associated with blood and therefore the life force. It's said to be harmful to ghosts, Fairies, Witches, and other supernatural beings. Hence hanging an iron Horseshoe over the door of a house keeps evil spirits out, an iron fence around a cemetery keeps the ghosts in, and burying an iron knife under the threshold of a house means witches cannot enter.
10. There may only be 100 years worth of mineable iron left on Earth. However, scientists have identified an asteroid in our solar system, 16 Psyche, which has enough iron to keep us supplied for millions of years.