If I have a piece of flat green glass from a 18th century historic site. How do I know if it is window glass or a fragment of case bottle? Roberta Charpentier Archaeology Lab Supervisor Mashantucket Pequot Museum and Research Center 110 Pequot Trail Mashantucket, CT 06339 Email: [log in to unmask] <mailto:[log in to unmask]> Phone: 860-396-6936 Fax: 860-396-6914