Is Carbon Hard or Soft?

Why are diamond and graphite so different if they're made of the same element?

by Janee' Harrison

In the general mineral exhibit of the Natural History Museum, I saw a lot of gems and crystals in cases, but I also saw a lot of graphite in cases next to the diamonds, and noticed that they are different even though they have the same chemical formula. When I use a pencil, I smell the graphite from the led and it smells like carbon. Why do graphite and diamonds look so different if they are made of exactly the same thing?

This is a picture of diamond by itself.

This is a picture of graphite.

The important compound of my project is Carbon. I chose to do Carbon because my project is dealing with Carbon inside of two minerals. Something that I know about Carbon is that it has the same number of Protons and Electrons which is 6. I also know that Diamond and Graphite are both made of Carbon that ONLY has ONE element in its chemical formula. Even though Diamond and Graphite have the same chemical formula, but they are different because they have different crystals structures. Diamond is formed with 4 covalent bonds and Graphite is formed with 3 strong covalent bonds so, this means that they are different.

This is the structure of diamond. This is the structure of graphite.

The different structures affect how hard and soft diamond and Carbon are. Diamond is hard because each Carbon has 4 covalent bonds than other Carbons. This means people can use diamond for cutting, drilling, and polishing other materials. Graphite is soft because it has 3 strong covalent bonds than other covalent bonds. This means that people can use graphite for writing. Graphite is so soft that when you press it against paper, it leaves graphite molecules on the paper.

Something new that I learned is that Diamond and Graphite aren’t the only minerals that has the same chemical formula but different color. Readers should always remember that even though diamond and graphite are different, they still have minerals that are similar. This is important because it can prove to people that everything is not always similar to everything else that you see around you. The next time you get to know new things about Diamond and Graphite, remember that you know how important Diamond and Graphite are in your own right.


Inorganic -- not made by living substances

Carbohydrates -- a group of large compounds

Translucent -- A substance allowing light, but not detailed images


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