Different shapes of amber are associated with its formation on the outside or inside tree trunks, where the resin gathered. By filling the empty spaces inside, larger, cohesive solids could be formed.

The most characteristic for external forms are drops and stalagmatic icicles, and the most sought-after ones – nuggets containing animal or vegetable inclusions. We find them especially in one of the types of amber, called layer amber, between layers of solidified resin. Trapped in an amber trap, they constitute an invaluable testimony of a life from millions of years ago.