This presentation will describe the structural characteristics as well as unconventional properties of engineered Au-Ag nanostructures. In particular these materials show unusual transitions to a highly conductive, strongly diamagnetic state. Structurally, these materials comprise of ~1 nm Ag nanoclusters embedded into an Au matrix. The presentation will emphasize synthesis, structure and optics. We will also discuss certain intuitive similarities with semiconductor nanocrystal assemblies.