For decades, scientists have relied on surface-sensitive measurements to understand how cubic hexaboride materials like cerium hexaboride (CeB₆) behave at the electronic level. But a new study suggests that these observations may not always tell the full story: surface rearrangements can fundamentally change what experiments detect. At first glance, CeB₆ has a simple cubic crystal structure yet, at low temperatures, competing quantum interactions give rise to unusual magnetic and electronic phases, making it a cornerstone material for understanding how electrons behave when they interact strongly with one another. For decades, it has therefore served as a model system in the study of strongly correlated electron physics. To probe this rich physics, researchers often rely on surface-sensitive techniques such as scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES). These tools allow scientists to map electronic states with atomic precision; however, new discoveries by M. V. Ale Crivillero (Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain), and colleagues suggest that such measurements may not always reflect the intrinsic behavior of the materials like CeB6. Surface reconstructions hide an electronic gap When a crystal is cleaved, bonds are broken; at the surface, atoms can rearrange to minimize energy, forming patterns different from those in the bulk structure. In CeB₆, this rearrangement appears to be the rule rather than the exception: in low-temperature, in-situ experiments, the team found that atomically flat, unreconstructed surfaces are extremely rare, typically extending only a few tens of nanometers. Instead, once the crystal is cleaved, most exposed regions quickly rearrange into new atomic patterns—known as surface reconstructions—before measurements are performed. This finding has important implications. If STM or ARPES measurements are performed on reconstructed regions—knowingly or not—then the observed electronic spectra may reflect surface-specific effects rather than intrinsic bulk behavior. On the rare