Gold pieces are the main currency in Swords & Potions. Usually it's shortened to gold with which you can buy items, recipes (except
"glowing" token recipes), improvements and pay for things in quests.
The amount of gold you have will be displayed at the bottom of the screen next to the clock. After you reach 1000 gold the will no longer display it in full, it will say 1K instead, and increase at 0.1K intervals. The exact amount of gold you have is tracked, and will be rounded (e.g. 510432 gold would be displayed as 510.4K). To see the exact amount, hover the mouse over the number and the game will display it in full (This works for most other numbers in the game that are rounded like this as well). This is the "standard form" of number display used in all edgebee games. When you reach 1000K the game will say 1M (million), 1000M is 1G (billion) and 1000G is 1T (trillion).