It is from the fossilised form of this resin (also known as amber) that the Cintamani Stone was formed, and its unique properties created the legend of the Stone, as well as the powerful Guardians that protected it.
Zoran Lazarević, the main antagonist of Uncharted 2: Among Thieves, consumed sap the resin is made from in the final chapter of the game, which healed the burned portions of his body and granted him superhuman strength, making for an extremely difficult boss fight.
Although there is no proof nor evidence of this, resin may have a distinct scent to it, as Nate often identifies resin by holding it up to his nose. How people came into possession of the resin outside of Shambhala is unknown.
Early in Uncharted 4: A Thief's End, it is revealed that Nathan Drake preserved a small vial with several pieces of fossilized resin in his collection. In the first interaction with the item he references how many men lost their lives trying to gain some of it in order to acquire power. It is also revealed that the solidified resin pieces glow when stirred. Years later, Cassie Drake finds the vial while rummaging trough her father's secret treasure locker, being puzzled by the presence of the resin in it.