- 1). Obtain limestone. That sounds silly but it's readily available in most areas and it's inexpensive. Try local rock quarries and hardware stores. It's sometimes used for landscaping.
- 2). Heat the limestone by roasting on an outdoor fire-pit. Cooking the limestone changes it chemically and physically. Allow the cooked stones to cool completely.
- 3). Dump a portion of cooled quicklime, quicklime is what you've created by cooking it, into a trough. Dump water on the quicklime. It will begin to hiss and a lot of heat will come off of the rocks. As the water is absorbed, the quicklime breaks down into a fine muddy mush (only it's white)
- 4). Add sand and pebbles to the new muddy mixture. You just made concrete, congratulations.
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