Ingots were masses of precious or semi-precious metal cast into convenient, generally oblong shapes for storage or transportation. They could be used as currency or currency reserve.
In the days of old, Republican Credits took the form of pure aurodium ingots. In the last decades of the Galactic Republic, those ingots were still used when a great amount of money was needed for trade. When Obi-Wan Kenobi was sent to Zonama Sekot in order to buy one of the planet's living ships in 29 BBY, he was given ten of these ingots for trade.
Piles of ingots, neatly stacked inside acceleration webbing, were found in the treasure room of the Vagaari plunder ship after it was captured by Commander Mitth'raw'nuruodo in the skirmish between the Chiss and Vagaari in 27 BBY.