Within the context of the Purari Delta’s transforming materialities of resource extraction, and the legacy of the Tom Kabu iconoclastic modernist movement (1946–69), I examine the processes of materialisation bound up with two related but different things: heirlooms (eve uku) and documents (Incorporated Land Group (ILG) forms). Eve uku (‘hand head’) lie within a continuum of things (names, relations, totemic ancestral spirit-beings and sites in the environment) through which ancestral actions are shown to have happened, and descent groups’ identities manifest. However, given the ambiguous status of the traditional past among the I’ai, the power of these forms is circumscribed to the village thus making them ineffectual tokens in the bid to secure royalties from resource extraction. Instead, highly coveted documents known as ILG certificates have emerged as efficacious things by which royalties can be secured. Examining these certificates as objects, I investigate how these documents help materialise anew descent groups, communities’ relations to their environment and thus their aspirations for development with its attending materialities. The problem for the I’ai, however, remains how to obtain these documents and, as with eve uku, how to control them.