You can consider buy a wild sprite from AH, it come with preset lvl of mining skill. I would suggest buy one that come with both forage and mining skills. Use it to collect materials to train your main guardian sprite.
We have 2 slots for wild sprites, use one for collecting materials, you can sell off excess material for some money. Use the 2nd one slotted with good emblems for picking of items while you are leveling your character. That way you can concentrate on training your guardian sprite and lvled it up in pace with your character. But er.. best prepare some soda or biscuits while you are training it, keep it always happy!