Things You'll Need
- Vinegar
- Rocks
- Water
Instructions
Obtain the rocks you want to test. You will find them either in streams or fields, at landscape supply companies or aquarium stores.
Pour a small amount of vinegar on the rock and wait. Keep watching it. If it bubbles then it indicates that the stone will break down in the water, or that at least parts of it might.
Soak the rock in water for several days to dissolve any contaminants that might be compromising the vinegar test. Replace the water occasionally so that the contaminants won't settle back on the rock.
Test the rock again. If the vinegar bubbles this time, discard the rock and try a different kind.