In my palm, I roll around three small stones taken from the waters. One is a blue schist pebble, slightly chipped, another a perfect egg of sandstone conglomerate and the last a pink and white granite sphere. When I force my brain onto the rack of geological time, exploding it out into a thousand ‘civilizations’ or so (my attempt at imagining a million years), then multiply this by, say, 50, I just about get an idea of each stone’s provenance. I feel I am rolling around three small planets in untouchable orbits; three lost worlds of breathtaking beauty, shape and form; elegant worlds which have been crushed, eroded, rolled into one another and, briefly, given this current page of a pop-up book: there you go, this is your planet for now; turn the page another million years and another world pops up. Stones are border guards of the unknown and secretive territories; bureaucratic knots in our states of understanding deep time . . . ...for the full article, visit the E-books page