I only just learned about these cool candles today, while pursuing one of my local buy/sell groups. If you were to purchase one of these from a candle store, they would cost somewhere between $45-$65 each. Find a cool rock yourself and it costs next to nothing. The best part is, the wicks last forever AND you can make them scented by putting essential oils in the reservoir. You’ll never have to buy yourself another wax candle again!
If you have a drill press, you can do this DIY. Honestly, I don’t know where one would find large, flat rocks like this, but perhaps you can buy them at a garden supply store if you can’t find them in nature. Check it out: