GrasbergIt looks like Grasberg started with about 30 million ounces of gold and 150 million ounces of silver and a lot of copper ( 1.2 %). The grade of ore is 0.5 grams per ton gold and 1.2 % copper and a good bit of silver. (unsure of gold equivalent value of ore). It has the worlds larget open pit at almost 2 km in lenght and produces about one million ounces of gold per year. Konkin may not be to far off in the comparison. That would be on hell-of-a royalty!