Plated Seashell Speaker
Similar to the paper speakers these copper plated seashell speakers are created by plating copper to a seashell that has first been painted with conductive paint where the copper should adhere. Running a 5-9V amplified sound signal through this coil and holding a magnet close to the center of the coil will produce sound. The sound is not loud, but this can be used intentionally, having to hold the seashell close to your ear to hear what it has to say.
For more details please see the paper speaker post: