That is a great way to clean old silver coins too. That is funny about bringing little bags of white powder through customs! LOL. A good way to go to the gulag! HH, Dave.
Oldest Coin: 100-60 BC Gallic bronze coin (Sequani Tribe)
Oldest Silver Coin: 1156 hammered Pfennig from (now) Bavaria
Oldest U.S. coin: 1805 Draped Bust Large Cent
Best Coins EVER: 1625 4 Sols from Kingdom of Chateau Renaud, France
1662 15 Kreuzers, Leopold I, Austria
Best Relics: Bronze Age Arrowheads & Spearhead, 2c Roman silver ring, complete medieval knight's spur (x6)
YouTube Channel: Full Metal Digger