You can mine gems using iron, I completely did not get the gold at all. Wood, stone, iron, then diamonds, like in minecraft. It's possible in the game to even mine gems using stone tools, since there wasn't any code for required types of pickaxes to mine the gems. Also, the boss isn't totally unfair, just stack on some regen pots and the tailsman, keep your distance from the boss when active, and you complete the game! Check my post below to see how I won the game!