  We have studied the magnetotransport of conical and disk-shaped nanocarbon
particles in magnetic fields $\left|B\right|\leq9\:\mathrm{T}$ at temperatures
$2\leq T\leq300\:\mathrm{K}$ to characterize electron scattering in a three
dimensional disordered material of multilayered quasi 2D and 3D carbon
nanoparticles. The microstructure of the particles was modified by
graphitization at temperatures $1600^{\circ}\mathrm{C}$ and
$2700^{\circ}\mathrm{C}$. We find clear correlations between the microstructure
as seen in transmission electron microscopy and the magnetotransport properties
of the particles. The magnetoresistance measurements showed a metallic nature
of samples and positive magnetoconductance which is a signature of weak
localization in disordered systems. We find that the magnetoconductance at low
temperatures resembles quantum transport in single-layer graphene despite the
fact that the samples are macroscopic and three dimensional, consisting of
stacked and layered particles, which are randomly oriented in the bulk sample.
This graphene-like behaviour is attributed to the very weak interlayer coupling
between the graphene layers.
