Collins uses personification to animate the Shivering Sand, a sinister patch of tidal quicksand on the coast of Yorkshire near the Verinder estate. The frightening stretch of moving, shimmering, changing ooze is so often described as having a "face" and making "expressions" that it almost acts as a character. When Betteredge describes the Sand in Period 1 Chapter 15, he observes that:
The inner sea lay lost and dim, without a breath of wind to stir it. Patches of nasty ooze floated, yellow-white, on the dead surface of the water. Scum and slime shone faintly in certain places, where the last of the light still caught them on the two great spits of rock jutting out, north and south, into the sea. It was now the time of the turn of the tide: and even as I stood there waiting, the broad brown face of the quicksand began to dimple and quiver – the only moving thing in all the horrid place.
The Shivering Sand is depicted as a dirty, slimy face, whose "broad brown" expanse "dimples" and "quivers" with the turning of the tide. The expressions of the Sand's "face" are uncannily changing and uncertain, as if it is a person whose motives are unclear. Usually, "dimples" would have been considered an appealing facial feature by a Victorian audience, as they suggest plumpness and kindness in a person's cheeks. However, the "dimples" on the sand are accompanied only by unpleasant things. The "dimples" on the water are part of what makes the Sand's "face" a "horrid place" to look at.
The sand is here and elsewhere aligned with the other "brown" faces in the novel, particularly that of the "remarkably" odd-looking Ezra Jennings, whose "dark" countenance is also described as ugly and difficult to read. This racist, xenophobic imagery of darkness and secrecy pairs the Sand with Collins's depictions of foreign characters, like Jennings and the Three Indians. Its malevolence and its uncertain motives are associated with the "malevolence" of non-English characters in The Moonstone, whose actions go largely unexplained to Betteredge and his companions.
