Magnetic display devices include low-density silica coated magnetic and
nonmagnetic particles. In a one-particle system, low-density silica
coated magnetic particles coated by a sol-gel process are used in
combination with non-magnetic particles. In a two-particle system,
low-density silica coated magnetic particles coated by a sol-gel process
are used in combination with low-density silica coated non-magnetic
particles. Display devices employing silica coated magnetic particles
minimize the tendency of the magnetic particles to aggregate. Silica
coated magnetic particles in a display device results in a magnetic
display with improved image stability. Low-density silica coated magnetic
particles in a display device allow for particles to move easily through
a dispersion fluid in response to a magnetic field.