I think the concept here is amazing! I like how you upgrade your dwarves as you mine more gems. What the game really lacked for me to truly put it through the roof was some sort of goal. If every type of dwarf had something they needed to do within one loop (like getting all the gem colors) that would be very nice.
Also really missed some sound and music, but the dwarves were cute, especially the mining animation. Deserves more ratings for sure!
Good game, would love to see it improved!