The Griffins just came by and I want to trade with them. I only need gold and 1000 Catpower, but I just need the gold. For the Catpower, I know what to do. I just need to get a lot of warehouses and barns. So... I just need help with the gold.
From the wiki:
After the Gold Ore upgrade, Smelters produce 0.001 gold per tick in addition to 0.02 iron for each 0.05 wood and 0.1 minerals.
After the Geodesy upgrade, geologists produce 0.0008 gold per tick.
After the Mining Drill upgrade, this amount is increased by 0.0005 per tick.
After the Unobtainium Drill upgrade, this amount is increased by 0.0005 per tick. In Iron Will mode, hunters can find gold.