More Herkimer diamonds

When I was a lad vacationing in upstate New York, I spent an afternoon at the Herkimer Diamond Mine digging up excellent double-ended quartz crystals. Only now, many years later, do I learn that you can also dig Herkimer diamonds at at least two other localities there, the Treasure Mountain and Crystal Grove "diamond" mines. (In the meantime I acquired my own real diamond grain at a rock show. This is it here.)