lava lamps?
It's a secret formula, but mainly, I think it is wax. Go to lava lamp's web site and see what info you can attain.
What does having a lava lamp mean?
Owning a lava lamp simply means that either a) you liked something about it (shape, colours, etc) so you bought it, or b) someone gave it to you as a gift. All kinds of people own lava lamps and it really doesn't say anything significant about them.
Who likes lava lamps?
I do I do! Loved them when I was a teen in the '70's and I still love them now. I have one that is red and orange and I love looking at it while listening to Pink Floyd.