I, like many others, play with the achievement part of the game to give explorers and geologists better skills to aid me in the game. I am therefore very surprised when the explorers bring back coal or fish plate as either an artefact or rarity find. These are not imo worth the effort in obtaining such skills. I believe after playing the game for a such a long time that a change should be instituted to give better finds. Come on BB give us some better finds - not coal and fish plates.