Set against the backdrop of past, contemporary and possible future mining-related violence on large islands in the western Pacific, this paper explores how theoretical work on sociospatial relations might sharpen our understanding of the political economic impacts of extractive resource enclaves in Island Melanesia. Taking up Jessop et al’s (2008) challenge of recognising the “polymorphy” of sociospatial relations, I interrogate the conceptualisation of Island Melanesia’s mining enclaves as islands within islands. While extractive enclaves can be seen as salient manifestations of the “spatial fixes” that attend globalisation’s dialectic of de- and re-territorialisation (Brenner 1999), they are far from being “starkly disconnected” (Fergusson 2005) from the socio-ecological contexts into which they are inserted. The profound sociospatial and political economic effects of enclave economies have been described for “mainland” contexts, for example in Michael Watts’ work on governable spaces and economies of violence in Nigeria. I suggest that islands, or more specifically the condition of “islandness”, provide especially potent containers for the sociospatial struggles that attend enclave economies.