Possibly a Window Pane. Transparent honey colored amber very bubbly glass with many impurities; surface partly covered with pitting, specks of brownish weathering, and on the reverse, brilliant iridescence; free blown; circular flat object, probably made in the crown method, with turned rim, the disc-like object having at its center, obverse, a slight depression from which a cone-shaped elevation rises, matching on the other side with a deep concavity having a rough pontil mark.