If you're reading this, the world did not end on December 21, 2012. Instead, you could be suffering either from post-holiday depression or from SAD (Seasonal Affective Disorder) caused by lack of sunshine. This last is especially true the farther north of the equator that you reside.
You could take anti-depressants or bathe yourself in artificial sunlight, but perhaps all you need is a lava lamp: "If you buy my lamp, you won't need drugs," advised the inventor of the lava lamp.
Inspired by a unique egg-timer he saw in a pub after World War II, British flyer Edward Craven Walker spent the next decade and a half developing and patenting the first liquid-motion lamp, the "Astro" lamp.
Walker formed Crestworth Ltd. and began manufacturing the lamp in 1963. In 1965 two Americans, Adolph Wertheimer and Sy Spector, impressed by the Astro lamp at a German trade show, obtained the exclusive U.S. manufacturing rights. The American version was christened the Lava Lite. It was the dawn of the psychedelic era, and millions of both the British and U.S. lava lamps were sold around the world. They even appeared on television series like Dr. Who and The Prisoner .
By the late 1970's, however, sales began to slide as fashions changed. Lava Lite was acquired by Haggerty Enterprises in 1976, and Crestworth managed to limp along until 1989 when Cressida Granger and David Mulley took over the running of the company. Granger, a graduate in art history and a dealer specializing in vintage 1960's and 1970's design, injected much needed energy and creativity into the company. Sales grew as new marketing and designs hit the market, and Crestworth became Mathmos in 1992. (Mathmos is named after the bubbling slime featured in the 1968 sci-fi film Barbarella.)
The success of Mathmos generated a resurgence of interest in lava lamps among both the general public and collectors. New lamps have been turning up everywhere as decorative statements in bedrooms, living rooms, and offices. And GooHeads, as collectors of the lamps are sometimes affectionately called, are often willing to pay up to several hundred dollars for vintage specimens, especially if accompanied by their original packaging.
Over the decades the lamps were issued in dozens of designs and variations which are easy to date according to stylistic characteristics and markings. For example, the very first Astro lamps were open under the base with an exposed green ground wire, while second generation lamps had metal plates underneath with a center hole for the wiring. Early Lava Lites had screw-type bottle caps with a dated sticker inside; later versions had bottle caps with the date printed on top.
The Lava Lite caps printed on top also carried a code indicating the color combination of the lamp. For instance, #09 indicated clear fluid and purple wax while #22 was blue fluid and purple wax. Rare color combinations included #11 (clear/neon yellow) and #23 (blue/green). (For a complete chart, check out the Oozing Goo site in the resource section below.) Something to consider when buying vintage is that prolonged exposure to sunlight could seriously have faded or changed the original colors of the lamp, a factor which could adversely affect its value.
Other factors to consider should you come upon a specimen at a yard or estate sale include general condition (is it broken or incomplete) and country of origin. Mathmos continues to manufacture its lava lamps in the UK, but Lava Lite moved its manufacturing to China in 2003 and quality has purportedly suffered to such an extent that collectors are loathe to invest in them.
And about that empty space at the top of the bottle: the lamp has not lost fluid. That gap you see is there to allow for expansion of the fluid when heated.
Would you like to find out more about this fun collectible? Check out the following list of resources, and
Chemistry Daily - Lava Lamp Good explanation of how lava lamps work.
Flowoflava.com Major site dedicated to the history of the British Astro (Lava) Lamp. Lots of pics, original ads, more.
Lava - The Original Official U.S. site.
Mathmos Official U.K. manufacturer's site also sells replacement parts for original lamps.
Oozing Goo - The Lava Lamp Syndicate GooHeads community site offers forum, member blogs, The Lava Library (FAQ's, Lava Lite Timeline, Models by Year, Light Bulb Table, Cap Codes), more!