The game prototype has been updated (0.3.7):

• Mineable deposits have been added! Big stone for rock mining, copper, sulfur and coal deposits.
• Pickaxe added for faster deposit mining
• Craftable Smelter to turn Copper Ore into Copper Ingots
• Bombs are now craftable (Ingot + Sulfur x2). Boms are now also more expensive in the shop.
• Sulfur can be added into a campfire to turn the flame blue for a short time
• Trees can now be replanted (Soil + Stick)
• Fight collision tweaks to fix wolf and boss getting stuck
• Misc small bugfixes and tweaks

Protip: a quick way to mine deposits is to use bombs :D

Cheers,

Matt