I wish to premise any advice based on I KNOW ABSOLUTELY NOTHING, however, my cutomers, who know EVERYTHING, have advised me on their ivory collections that I must put a dish of water in the glass display case with the pieces to prevent this sort of thing. You might want to see if there is anything to it. . .I just do what they ask me. . . Charissa Lee 71-550 Highway 111 Rancho Mirage, California 92270 619/568-4627 619/568-3148 FAX [log in to unmask]