How can architecture be geometrically complex yet socially active? How can we envisage architecture that develop social relevance as much as aesthetic and experiential quality? How can geometric and experiential articulations support a civic sense within building? To this the crystalline form of Calcite, native to the shores of Hastings, was explored for its spatiality through a series of quasi empirical experiments, and its sensory effect tested with the aim of discovering a geometrically-rich vocabulary that may be extended into reality. A competition brief for an art gallery at Hastings, Sussex, served as the context to pursue this interest in complex geometric spaces with civic sense.