I’ve owned this for about 10 years and bought from an estate. I would guess that it’s a 1980′s or 1990′s design. I can’t say that this actually qualifies as slag or stained glass as it is not an antique but that’s the style it represents. The lower panels are very thin and very fragile, likely why the one side panel has been broken. I would guess glass there is maybe 1/16th of an inch thick. They are a bit tricky to get in and out and and gentle delicate hands will be required to remove or replace them. That is also where the lower bulb is located. The top tier lighting has two bulb sockets, the lower base section just one. Working 3 way switching mounted on the base. Some of the wood is nicked there that can be seen in photo’s. The top lights, the bottom lights, and they both light together. This is a very beautiful lamp and is not used and not perfect. If you have any questions please feel free to ask. It’s about 27 inches high to the top finial and the shade is 18 inches long and 10 inches wide or deep. Item listed is used. It has been owned by an unknown number of previous owners and as such may have ended up in a basement, garage, attic, or shed as sometimes over time things fall out of favor. Price is non negotiable after action has ended. The item “Vintage Frank Lloyd Wright Style Mission Arts and Crafts Slag Stained Glass Lamp” is in sale since Thursday, February 25, 2021. This item is in the category “Collectibles\Lamps, Lighting\Shades”. The seller is “thebabyloncollection” and is located in Muskegon, Michigan. This item can be shipped to United States.