Earths Magnetic Field

It is notable how much static electricity
can build up from the falling of various
sized water droplets in a thunderstorm.

Basic questions:

What are the electrical conductivity
properties of the both the solid
and liquid cores at such high
temperatures and pressures?

Are there significant differences
in the electrical properties of
the two types of core and
intermediates?

What are the electircal properties
of the junctions between the
liquid metal core and the semisolid
magma mantle? Is magma at such
high temperatures and pressures
still going to be an insulator? What
about magma with a high level of
liquid metal embedded in it possibly
as a metal droplet ('aerosol'?) or as
metal complexes with partially
dissolved magma impurities.

Is magma going to be be withdrawing
electric charge from the liquid metal
core, or adding charge to it? Are the
electrical junctions at the magma-core
boundary significant when it comes to
the earth's magnetic field? What would
be the likely electrical and magnetic
properties of magma particles flowing
and being carried by the physical movement
of the liquid metal in the outer liquid
metal core? Is the magma-core boundary
significant when it comes to geomagnetism?

On a non-electrical side note, is the more
solid inner metal core generally plastic?
Would it allow the migration of heavier metal
components further toward the center.
(Effectively concentrating lead, uranium,
and the heavier metals toward the furthest
and lowest interior?)