Most Baltic amber is found in Eocene glauconite deposits, known as blue earth.
Significant deposits are located under the bottom of the Bay of Gdańsk, on the Sambia Peninsula (Kaliningrad Oblast, Russia), in eastern Poland (Lublin Region), eastern Germany and western Ukraine.
These are coastal marine sediments that had formed near the mouths of rivers which took the pieces of resin into the sea. However, Baltic amber can be found virtually all over the North European Plain due to the Ice Ages, when some amber-containing sediment was pushed away of by the ice to be washed out by the rivers.
On the Baltic beaches, amber can be most frequently found after storms. The waves wash it out of the sediments and the currents move it to the beaches along with sticks and tree remnants.