Shape-based search of a collection of content associated with one or more images of inventory items (“inventory images”) is enabled at least in part by associating the collection of content and/or its associated inventory images with representative refinement shapes. Inventory items may be grouped into categories and at least one refinement shape may be created for each of the categories. A refinement-shape hierarchy may be created by arranging the refinement shapes into parent and child refinement shapes. Inventory images may be associated to at least one of the refinement shapes of the refinement-shape hierarchy based at least in part on similarities between the refinement shapes and shapes of the inventory items reflected in the inventory images.