  A brief overview on high-pressure synthesis of superhard and ultrahard
materials is presented in this tutorial paper. Modern high-pressure chemistry
represents a vast exciting area of research which can lead to new industrially
important materials with exceptional mechanical properties. This field is only
just beginning to realize its huge potential, and the image of "terra
incognita" is not misused. We focus on three facets of this expanding research
field by detailing: (i) the most promising chemical systems to explore (i.e.
"where to search"); (ii) the various methodological strategies for exploring
these systems (i.e. "how to explore"); (iii) the technological and conceptual
tools to study the latter (i.e. "the research tools"). These three aspects that
are crucial in this research are illustrated by examples of the recent results
on high pressure - high temperature synthesis of novel super- and ultrahard
phases (orthorhombic gamma-B28, diamond-like BC5, rhombohedral B13N2 and cubic
ternary B-C-N phases). Finally, some perspectives of this research area are
briefly reviewed.
