I believe it is a location glitch with the game. I also had trouble with finding the gold under the icon. Never went back to the relic place, because I had already been there. I seem to remember picking up gold when I got the relic. I saw a video of the problem and went back to the relic location above the fire at the end of the swim from the dyer's house. There was 5 gold on the floor near the fire, which I picked up (Again?? pretty sure I wouldn't have missed it the first time). But, when I activated Survival skill with the gold icon 'selected', it showed the gold icon still white -- but across the room under the mat of sticks. I pulled down the mat this time and climbed out in case the gold actually does respawn and it will be easier to check without doing the swimming. I believe a game programmer put the achievement marker in the wrong position when coding, which might keep you from being able to clear the achievement even though you have picked up the gold in the other location. I for sure have picked up the 5 gold (maybe twice), but the icon is still white on the Map. Hope this helps.