  The review is devoted to a discussion of new (and often unexpected) aspects
of the old problem of elastic light scattering by small metal particles, whose
size is comparable to or smaller than the thickness of the skin layer. The main
focus is put on elucidating the physical grounds for these new aspects. It is
shown that, in many practically important cases, the scattering of light by
such particles, despite their smallness, may have almost nothing in common with
the Rayleigh one. The so-called, anomalous scattering and absorption, as well
as Fano resonances, including unconventional (associated with the excitation of
longitudinal electromagnetic oscillations) and directional Fano resonances,
observed only in a small solid angle, are discussed in detail. The review
contains a Mathematical Supplement, which includes a summary of the main
results of the Mie theory and a discussion of some general properties of the
scattering coefficients. In addition to purely academic interest, the phenomena
considered in this review can find wide applications in biology, medicine,
pharmacology, genetic engineering, imaging of ultra-small objects,
ultra-high-resolution spectroscopy, information transmission, recording, and
processing, and many other applications and technologies. The reported study
was funded by RFBR, project number 19-11-00001 and the project of the Russian
Science Foundation No. 19-72-30012, within the framework of which all the
original calculations given in this publication were performed.
