One thing to keep in mind is that if the ore body is roughly the shape of a cylinder, increasing the width or diameter from an average of 300 feet to 600 feet QUADRUPLES the amount of ore within the deposit, all other things being equal.
The formula for the volume of a cylinder if I recall is Height times pie times the square of the radius. The radius is 1/2 of the diameter. So this deposit could be the equivalent of four ordinary deposits.