Printable Seashell Mask

5 Interesting Facts About Seashells!

• Seashells are the exoskeletons of molluscs - they're not a separate structure that the animal lives in but literally part of the animal's body, secreted from a layer of tissue called the mantle.
• Shells grow by adding material at the opening edge - the characteristic spiral shape of many shells is the result of growth at a constant rate in a single direction, producing the precise mathematical curve known as a logarithmic spiral.
• You can't actually hear the sea in a seashell - what you hear is ambient sound resonating inside the curved chamber, amplified and filtered to create an ocean-like rushing sound. It works just as well with a cup over your ear.
• Shells have been used as currency across the world - cowrie shells were used as money across Africa, South Asia and parts of China for thousands of years, and were one of the most widely traded objects in the ancient world.
• Some shells are extraordinarily valuable - a rare cone snail shell called Conus gloriamaris was once so prized by collectors that a painting of the shell sold for more than Vermeer's Girl with a Pearl Earring at the same auction.