The results of the multi-year monitoring of the state of Saint
Petersburg stone monuments are summarized. The unique collection of decorative
stones in museum Necropolis and the deposits that were most likely used
to create them are studied. The processes of stone monuments’ degradation in
response to physical, chemical and biogenic influences are discussed. Special
attention is paid to describing the monitoring methodology and the structure of
the monitoring information database. Drawing on received results, the strategy
for the conservation and restoration of monuments are discussed. The obtained
data are of exceptional scientific interest in studying the processes of stone
deterioration under the impact of the environment.