With the exception of "Refugee Tools". In order to harvest mats over Level 50, you need to have the skill level and the pick appropriate for that level. Pick and tools may be bought from the Tool Merchant or crafted at Level 50, 100, 150, 200 and 250 ... a level 100 pick / tool allow you to dig up to level 100 mats and craft up to level 100 crafts.