Since I live in Latvia I feel myself responsible to answer the amber
part of this question.
1) Most of the Baltic amber reaching the international market comes
from the Russian enclave, the Kaliningrad region (former Koenigsberg
in Prussia) between Lithuania and Poland. Small quantities of the
original mass have been washed out in prehistoric times and appear as
sediments near the Baltic sea in Latvia, Lithuania, Poland and even
Danmark, but these are mostly for amateur diggers. The vein from the
Kaliningrad region continues on the continental shelf and is washed
out, especially during strong winter storms and a seizable amount
drifts northward to Lithuanian/Latvian shore. It is collected by
professionals and a small percentage may remain in the beach sand for
people to find and enjoy.
2) The industrial quantities come from the Yantarnoye (Palmiken
before WWII), where they are washed out from the "blue earth" layer,
some 40 mil years old sediment in a way not much different from any
industrial ore production.
3) In Soviet period all production was strictly controlled and the
pilferage was "amateurish". At the end of 80s the diversion was more
noticeable, since people were allowed to own hard currency and
everybody was interested to sell something for hard cash. Legends
persist about the Kaliningrad fishermen exporting barrels of
"herring" to Poland, filled with amber. Before the breakdown of the
USSR the "export" to Poland's black market was so spectacular, that
prices dropped and amber became available in unusually large pieces.
4) I am not very well informed about the present market, but any
attempts by Russia to control the supply and prices might be futile,
given the amount in Polish hands and already stocked in the USA.
5) It is presumed that the Soviets treated Baltic amber as strategic
material due to exceptional properties of amber laquers and did not
export raw material, thus keeping the prices high. This point
requires some research to be sure.
Eddie "The Chemist" from Latvia