Looks like it could be camp lead. The top photo has the indication of lead to surface or ground contact when it was initially melted. The bottom photo looks like a smooth puddle. I have found many pieces of melted lead and it can take on many forms and shapes. If there was any human activity in your area then there is a possibility that it is camp lead. Type of activity in the area and corrosion/color of the lead are the best indicators of how, when and why it got where you find it.