@inferno-mayhem7
Well, Sir , during my many Adventures on the Sea i was 7 times lucky to find an Ancient Skeleton...Two times i was so excited ( * and you just couldn't hide it …? ) that i fell of a rock and the Skeleton dove into the ground like a mole...i can't say the average of what i caught since i have forgotten the exact amount but ...i remember the lowest amount , some 158 coins and the highest amount which was around 473 coins , so it could be that you need some 2 skeletons to buy a pet...
But Grinding...hmmm...i wouldn't recommend it ...Just buy a map and stop by many islands to find resources , treasure and who knows what else , and if you're lucky they will come out of the ground , but ...don't hesitate too long , be fast and swift and use that sword so you can delay his departure into the ground again...Allthough the amounts aren't going to make you rich , it is always thrilling to see and hear the Ancient Skeleton appear…
So ,just play ,visit many islands , stroll on there , keep an eye on the horizon for incoming Pirates , and tune yer eyes and ears like a cat , they are there but are quickly gone...Go for it.