  In this paper we study the 6d localized charged matter spectrum of F-theory
directly on a singular elliptic Calabi-Yau 3-fold, i.e. without smoothing via
resolution or deformation of the entire fibration. Given only the base surface,
discriminant locus, and the $SL(2,\mathbb{Z})$ local system, we propose a
general prescription for determining the charged matter spectrum localized at
intersections of seven-branes, using the technology of string junctions. More
precisely, at each codimension-$2$ collision of seven-branes, we determine the
local seven-brane content and compute the number of massless string junctions
modulo the action of the $SL(2,\mathbb{Z})$ monodromy. We find agreement with
the predicted results from $6$d anomaly cancellation in all cases considered.
Examples include a generic Weierstrass model with arbitrary Kodaira fiber
intersecting an $I_1$, as well as cases with jointly charged matter localized
at intersections of non-abelian seven-branes.
