Artisan Archive

I recently picked up Artisan and decided to do an artisan mission. I selected one for a Metal Resource and the Efficiency was 68. So i decided to head out to the wilds of Tantooine to find a metal concentration of 68%. I traveled out to around 1200 meters and started sampling and you know what.... nothing happened... !! Was i supposed to be looking for a specific metal? IF so, where does it tell you what you are supposed to look for? How much of it am I to collect? All these questions have prevented me from finishing it so any help on this matter would be greatly appreciated.

Thanks