Lava lamps serve as a decorative light fixture.
A lava lamp is a decorative light fixture that provides an entertaining display of lava-like liquids interacting with each other in a tapered, glass body that is softly lighted. When heat is applied to this system by an electric coil and/or incandescent light bulb, these interacting liquids resemble a lava flow as globules of soft wax-like substances rise and fall with the heat-induced convection currents within the lamp.
The lava lamp was invented in 1963 by an Englishman named Edward Walker, who piloted spy planes during World War II and was a dedicated nudist. He originally called his invention the Astro Lamp.
The lava lamp quickly became a must-have item for the younger generation of the 1960s, and these lamps adorned many dormitory rooms and campus dwellings of that era. Over the years, lava lamps have attained iconic status for that generation.
The science of the lava lamp is relatively simple. It begins with a translucent or clear glass container that has a source of soft light and heat incorporated into its base. This tapered bottle is filled with several liquids of varying densities. When heat is applied to this mixture, convection currents are created within the container and a fascinating interaction between the different substances is generated.
The traditional lava lamp mixture usually consists of water, soft wax, carbon tetrachloride and up to 14 different proprietary chemicals. Assorted coloring agents are also added for artistic effect.
The base of a lava lamp has a light source and often an electric heating coil. When these heat sources are turned on, the soft and energetic light show for which lava lamps are so justifiably famous will ensue.
At room temperature, the density of wax is slightly greater than that of water, and at elevated temperatures, the density of wax is slightly less than water. This means that the heated globs of soft wax tend to rise to the surface of the enclosed system when heat is applied and descend to the bottom when they cool off.
This basic lava lamp process was further embellished by having discrete granules suspended in the enclosed liquids. These granules could often look like precious gems or a star-studded night sky circulating in the lamp.
The lava lamp lost most of its hold on popular culture during the 1980s, which was caused, to a great extent, by a British Broadcasting Corporation (BBC) report that claimed chemicals used during the production of lava lamps were toxic to the environment.
In 1989 all rights for the lava lamp were purchased from Edward Walker by Cressida Granger, who was a former art student and owner of a small antique shop. Granger founded a company named Mathmos to market lava lamps anew, and by 1999 Mathmos had grossed an impressive $25 million in sales for the reintroduced icon. The word, Mathmos, was taken from the cult film Babarella and refers to an evil force bubbling beneath the surface in the film.
As of 2009, the lava lamp as a decor item generally serves more as a nostalgia device, or as a prop in a room, home or building that utilizes themed decorations.
In a new and innovative twist on the traditional model, giant lava lamps are now available at many retail outlets. These lamps hold up to 250 ounces of bubbling imitation lava and can be 2 to 3 feet tall. They can be found at Cool Stuff Cheap.
As nostalgia waxes and wanes for the 1960s and 1970s, lava lamps can be purchased at commercial outlets that cater to the intermittent resurgence of interest in the artifacts of this era. For example, Generationstore, stocks a selection of icons and products that date back to these decades.
Lava lamps can also be purchased from modern, upscale outlets that provide a range of merchandise. Some of these outlets, such as Planet Lava, have a large selection, including a variety of sizes, colors and decor options.