How much gold has been mined in human history?
It's hard to believe, but if all the gold ever mined was weighed, it would amount to between 140,000 and 160,000 tons. That would be a cube of approximately 62 feet on a side. A cubic inch of gold weighs 11.06 oz.
Yes there would, if there is gold in the ground now there would have been gold in the ground then (the middle ages weren't that long ago!) Because gold reacts slowly, if at all, the gold that is on the earths surface now would have been there then. BUT not all the gold was mined, so in answer to your question, yes there were mines but different to the ones of today.