The metallic bond consists of a series of metals atoms that
have all donated their valence electrons to an electron
cloud that permeates the structure. This electron cloud is
frequently referred to as an electron sea. It might help to
visualize the electron sea model as if it were a box of
marbles that are surrounded by water. The marbles
represent the metal atoms and the water represents the
electron sea.
Kernels
Since the metal atoms have all lost
their valence electrons, they are now
positive ions. However, because they
are not associated with ionic bonding,
these  positive ions have a special
name. The  positive ions within a
metallic solid are known as Kernels.
Metallic Bonds  - Streaming