Crystal Acrylic Shell Lamps

The acrylic-base night lights (Figure 23) are our personal favorites of all the giant clam shellcraft items described in this manual. Consider these attributes: they are relatively easy to make, they command a hefty retail price ($24.99), and they are truly lovely to behold in a darkened room. They are durable, compact and easy to transport. In short, they are the perfect gift item for tourists and the perfect Christmas present for their family members. It is no wonder that these were one of the most popular items ever sold in the MMDC Gift Shop. The only conceivable disadvantage of this product is that its construction requires a component, the lamp base, that must be imported. This entails up-front materials costs that are not characteristic of most of the other items in this manual.

The acrylic bases (Figure 24) used for these lamps are distributed by a California company called Venus Displays. Contact Venus directly for a price list and catalog. We found the 3-inch, square acrylic base to be the most practical for giant clam lamps; however, other sizes are available. The base unit includes the 7-watt lamp, socket, wire and switch, and cost about $4.50 each wholesale in 1994.

Use paired shells in the 12 to 15 centimeter size range for making these lamps. Process the shells by chemical bleaching, followed by an acid dip. Grind the base of the shell pair, near the byssal opening, until flattened. Then grind out a circular opening about 3 centimeters in diameter, through which the bulb will pass. After rinsing and drying the shell pair, glue it carefully to the acrylic base using a hot glue gun. The base can accommodate a small sticker identifying your company; better yet, consider attaching a printed “hang tag” that bears a little background information on giant clams.

T. squamosa shells (Figure 25) make the most beautiful shell lamps. Unfortunately, they are considerably more difficult than the other species to clean properly, and the flutes or scales on the shells are prone to chipping, which lowers the value of the finished product. H. hippopus shells, on the other hand, are much easier to clean and have the added advantage of being virtually indestructible. In our opinion, they are the best all-around species for giant clam shell lamps.

The value of giant clam shell lamps seems to be closely linked with the richness of the colors in the shells. Clam farmers can and should influence the colors of the shells in land-based tanks by culturing herbivorous fish with the clams. One hypothesis for which there is good supporting evidence says that certain pigments in the waste products of the fish are deposited in the protein matrix of the clam shells, creating the rich yellow and reddish-brown hues one finds in T. squamosa and H. hippopus, respectively. Good herbivorous candidates for polyculture with clams are rabbitfish and surgeonfish. If you are a clam farmer and have not discovered this already, try fish-and-clam polyculture to see if it does not enhance the color and value of the shells you produce. As an added benefit, it will also greatly reduce algal fouling in your tanks.