Diamonds are the state gem in Arkansas, where we live, but students everywhere will enjoy learning more about them. Diamonds are made entirely of carbon — we humans are about 18% carbon ourselves, but diamonds are all carbon. They’re the hardest substance in the world, and they reflect light in a special way (basically, the light bounces around inside the diamond) that makes them super shiny.
How diamonds are formed
- Diamonds began with stardust. As far as we know, pretty much all the carbon in the world came to earth as dust from dying stars. The stardust that ended up deep within the earth was the starting point for diamonds.
- The carbon inside the earth’s layers, between the core and the crust, got cooked and squished — it takes a lot of heat and pressure to create diamonds.
- When magma comes up to the earth during volcanic action, diamonds can come along for the ride. The results is areas where diamonds can be mined, as in the book at the Volcano Lesson Plans link, and also diamonds moved around by erosion.
Have students conduct research on each of these steps and create an infographic showing how diamonds are formed.
Read about Crater of Diamonds State Park, where diamond hunters can keep any diamonds they find — and large diamonds have been found there, including the “Uncle Sam” diamond, which was over 40 carats. Crater of Diamonds is the only active diamond mine in the United States, but it is operated as a tourist attraction; it was found that it could not be operated profitably as a commercial diamond mine. Download the Teachers Guide for reproducibles (reading comprehension passage, maze, and word find).
Plan an imaginary class trip to the park, figure the costs, and determine what sort of diamond the class would have to find to make the trip pay for itself. This project will give practice with online research, math, and problem solving.
Share A Diamond’s Journey , an interactive digital presentation from NBC news, with older students. There they can follow the diamond from the mines in Africa through cutters in India to sales in Europe and the United States. Have students create a chart showing the cost of a diamond and how much of that price goes to the miners, traders, cutters, and dealers.
Compare the Crater of Diamonds park and the commercial diamond mines. Discuss why a diamond mine in the United States might be harder to pay for than a mine in Botswana. Will American workers accept jobs like those of the miners in the Congo or the cutters in India? Would it be legal to pay an American worker $65.oo per month, the wage diamond cutters earn in India, or to have them live in tents at a mine?
The value of diamonds
Gem-quality diamonds are the first ones we think of. Have students explore Blue Nile’s Diamond Education section to learn about diamond shapes and the “4 Cs” of diamond quality: color, clarity, cut, and carat weight.
Don’t miss the chance to work with ratios on the Diamond Shapes page and measurement on the Cut page!
Now learn about diamonds as they are used in jewelry:
- Read about the history of diamond cutting and add the times and places to your class timeline and map.
- Explore a Pinterest board on diamonds which shows many of the most famous examples of diamond jewelry in history.
- Have students design a piece of jewelry for diamonds, being sure to incorporate what they’ve learned about diamond quality and cutting.
Wait — diamonds aren’t just for pretty! Only a small percentage of diamonds are gem quality. Most are industrial quality, but they are still extremely useful. Diamonds have some special characteristics that have nothing to do with their beauty:
- Diamonds are the hardest substance known.
- They do not conduct electricity well (they are semiconductors), but they do conduct heat very well — in fact, diamonds are the best material for thermal conduction.
- They resist water, but accept oil.
Brainstorm with the class situations in which objects with these characteristics might be useful. Share with students (after brainstorming) that diamonds are mostly used for cutting and polishing. However, there are many other uses for diamonds. For example, diamonds are used in micro-electronics to carry heat away from delicate machinery. They are used as bearings (like a ball bearing) in watches, because they are so hard that they produce no friction in this use. They are used as semiconductors in electronics.
If the point has not yet come up in your discussion, point out that diamonds are small and rare. As long as industry needed big pieces, diamonds were not as useful as they might have been. Now that we make very small things for electronics, diamonds are very useful.
99% of the diamonds used in industrial applications are synthetic. See the links below to learn more about making diamonds.