Mercury's surface composition is being mapped through multispectral imaging tech. Different wavelengths reveal distinct mineral signatures, letting researchers trace which materials formed during the planet's early differentiation vs. later volcanic activity. The spectral data shows iron-poor minerals dominating the crust, suggesting Mercury lost its outer silicate layers early in formation—possibly from a massive impact that stripped the mantle. This mineral mapping directly informs planetary formation models and helps explain why Mercury has such an unusually large iron core relative to its size.