This article examines the making and makers of "memorial diamonds." These are "natural" diamonds identical to gemstones found in nature but produced in laboratories with carbon sourced from genetic material (cremation ashes) or other objects of symbolic and emotional value. Threading corporality and objectified life forms, we examine the transformation from ashes to the "afterlife" of these "living" objects that are at once synthetic and organic. We ask, first, what material and affective properties distinguish synthetic diamonds from those extracted from nature? Second, how are these living and memorialized representations of inert substances – in continuity with bodily elements of the deceased – valued and mediated through "real" human, though artificially grown, natural objects? Drawing from research with the leading companies in the memorial diamond business in Switzerland and the United States, this article suggests that these diamonds’ singular connection to the human body offer a window into the transmutations between nature and the artificial, memory and material likeness, life and death.