Traveling the world on grains of sand. It sounds like a mythical concept, but it’s the essence of psammophiles, sometimes called aerophiles. In plainer English: sand collectors, referring to those who gather sand samples from around the world, focusing on the grains’ textures, colors, mineralogy and, most of all, places of origin.

Worldwide, sand collecting is a hugely popular, albeit quietish hobby. It can be as involved as proponents care to carry – or send – it.