Free write: A Rock

Here is the beginning of a story. What would you write next?

Evan stood on the beach facing the grey inhospitable sea. At the farthest distance, the rough woolen sky was separated from the clay-coloured ocean by the merest smudge of a horizon line. In the middle distance, the ocean was like stippled granite. Then closer to him, grey-green waves with foamy tops rose up and raced toward him up the beach, stopped just short of his dirty canvas runners, then slid back down carrying away little rivers of beach pebbles.

Pebbles. Rocks. In his pocket, a weight against the top of his thigh. A rock. A rock like the heat of an egg yolk, an eyeball, a heart pulsing in his pocket. . . .