Cranberry oil lamp chimney. approx 11 3/4" tall , 1 3/8" top, 1 7/8" at bottom, bulge area about 2" high. I got this at an auction from lady who wrote books on student oil lampsso assuming its for student lamp. I really do not know. color is real dark so i do not know why used for oil lamp unless for photo lab or something. it does have a sliver chip on bottomas shown in pic on outside and another real minor one on inside right near base probably caused by burner. extreme light waving can be felt in parts of glass shaft i guess due to poor glass making back when manufactured. nothing to worry about just not perfect like newer chimney's would be. I will look at all offers as i really am not sure of its value. no etched marking anywhere on chimney. email any ? make sure you want before bidding as no refunds. chip can best be seen in last pic along with water drops from washing.