Because the way they glow and how if you buy a red one it looks like lava. I say that the part that moves is the lava, and the liquid when lit with the light bulb turns into a lamp. as you can see in...
Colored paraffin wax and waterThe lava in a lava lamp is made out of oil, water, and carbon tetrachloride, commonly used in fire extinguishers.
No there is NOT real lava in lava lamps. If there was real lava in lava lamps, it would burn, it just oil and water.
Oil and wax.
Water, wax, and carbon tetrachloride.
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