  Let $\vartheta := \frac{-1+\sqrt{5}}{2}$ be the golden ratio. A golden
lattice is an even unimodular $\Z[\vartheta ]$-lattice of which the Hilbert
theta series is an extremal Hilbert modular form. We construct golden lattices
from extremal even unimodular lattices and obtain families of dense modular
lattices.
