This paper widens the metaphor of shells beyond merely a static defense, to include the dynamic activity of psychic calcification. Autistic functioning is explored in the literature and as a part of the analytic encounter, for both patient and analyst. Freud's theories of the contact barrier and the mystical writing pad and Bion's idea of archaic remains are presented and combined to form an active, palimpsestic model of the psyche. In this model, microscopic movements matter. The author presents two challenging cases that illustrate the importance of patience and attention to micromovements when we are alerted to calcification in the here and now of clinical work.