Most people think beach sand is pretty generic and that one beach is much like another to build a sandcastle on. But when you get down to the nitty gritty of it the sand on different beaches can be night and day, even along the same side of the island.
Our pink sand grains come from a special type of coral called Forminifera that grow out on the reef line. It is broken down into to smaller pieces by wave erosion or parrotfish, mixed with other shell particles and deposited by the tide and waves on the beaches.
Parrotfish are a protected species in Bermuda as they play an important part to keeping our coral reefs healthy and algae free. Scraping their sharp teeth over the rocks they consume all the algae and sponges that threaten to smother the coral, and excrete out the left over rock and shell bits after. One parrot fish can create up to 15 pounds of sand in a month.
Not all of the sands deposited are good for building castles. The type of sand found on each beach depends on many different factors including, how close the reefs are to the shore, wave and tidal action, wind directions etc.
Because the pink particles are denser and heavier than the shell pieces they are found in higher concentrations along the water line where the waves tumble them over and over until they are fine enough to be washed up the beach. There they are picked up by the wind, blown into dunes and bleached by the sun. This is why you will find the sand much pinker down at the water line rather than higher up the beach
When building sand castles the finer and wetter the sand the better. It is the water tension between well compacted fine sand gains that holds you castles shape. Beaches with coarse large grained shell sand are almost impossible to build a decent sandcastle on. The best test for your beach is to create a sandball with a scoop of wet sand and small amounts of dry sand pressed together in cupped hands. If your ball holds its form and you can toss it back and forth between both hands you are ready to create a masterpiece. The best beaches for sandcastles in Bermuda are, Horseshoe Bay(home of the Bermuda Sandcastle Competition), Elbow Beach, John Smiths Bay and Clear Water Beach.