I turned out one of my pockets earlier and dumped half a handful of sand all over the floor. This isn't an uncommon scenario - not only does sand get in my pockets, but it seems to end up in my wallet, fill my socks (when I wear them), and sometimes rains down from my hair when I shake my head. Ordinarily it's a massive inconvenience, but today I realised just how good sand is and how important it is to me. I'd miss it if I didn't spend each summer with my bed full of the stuff.
Sand is different all over the world, and if you look at a load of it through a microscope each grain varies enormously from the next. It's just ground up bits of rock and minerals, with the most common constituent in temperate latitudes being silica in the form of quartz crystals (which look incredible through a microscope), whilst in the tropics calcium carbonate from ground up coral reefs and shellfish make the beaches tour-brochure white. Black sand is normally found on coastlines where there is a lot of volcanic basalt rock.
Sand moves around a lot, and not just by hitching a ride in my pockets. In the littoral zone waves push it up the beach and pull it back down, shifting untold amounts of it along shorelines each year. This movement of sand forms the lumps, bumps, and eventually the sand banks that cause waves to break on the beach, so you can see all of a sudden where my appreciation for the stuff comes from. There is nothing quite so good as some well organised grains of sand. Whilst on a University field trip five other students and I had to try to hold a sand trap in a French shorebreak to assist with research into the movement of sediment. We had to keep repeating the measurements, however, because each successive wave knocked at least four of us off our feet and washed us and all of the apparatus up the beach on our backs. Sand also carries well on the wind, as can be seen in the Pyrenees where the south facing sides of some of the mountains are tinged yellow with sand that has been blown north from the Sahara, and it's even been said that Saharan sand has, on occasions, fallen from the skies over South America having been carried by the trade winds across the Atlantic.
Sand is pretty special stuff. We once used it to measure our most precious resource - time.
It covers massive areas of our planet both above and below the water and has a big role in shaping how we have fun, whether with a bucket and spade building sandcastles on the beach as grommets or by facilitating how the waves that we surf as adults break. For that, I can deal with having to tidy up the piles of it that fall from my body and clothing at regular intervals.