Tesserae are some of the most ancient geologic units on Venus and, as such, record the longest history of surface evolution. Their composition and formation mechanisms are still debated, and the degree of variation in their surface properties is not fully characterized. Here we use Magellan synthetic aperture radar data to calculate backscatter coefficient variations throughout 22 tesserae distributed latitudinally and longitudinally across Venus. Statistically significant variations are identified between tesserae, which can be divided into groups smoother (64%) or rougher (36%) than a tessera average. The backscatter coefficient variations of at least one-third of smooth tesserae are controlled by post-emplacement processes, specifically the deposition of fine-grained impact ejecta. It will be critical for upcoming missions to consider both original morphology and post-emplacement processes when evaluating the rock types and diversity of tesserae.