I keep my bronze halfpennies in capsules in a cabinet, they look rather nice . I haven't encountered any problems at all with this method, no verdi gris or new carbon spots have appeared. Also, it prevents other coins from being 'infected' by verdi gris or cabon spots. I would reccomend this method to anyone, just make sure that you ask peter to make the insersts deeper to accomidats the capsules, he was fine with it when I asked him to do it for me