Looks like a tailings dam to me, containing waste materials from the mine after processing. The solution has partially evaporated leaving a salt residue. At le

Looks like a tailings dam to me, containing waste materials from the mine after processing. The solution has partially evaporated leaving a salt residue. At least thats what it looks like to me. I don't think its a raised pyramid like the other reply says, pretty sure it is a hole. If you do a google image search for 'tailings dam' you see some things that look pretty similar...