Ok everyone, I have an interesting problem. I have some Erwin Lambeth chairs (spider back) and Im not sure what they are worth and how to prove their authenticity to a potential buyer. There are no tags or markings that I can see. I know the bottom of the chair (I can't remember the technical term for that material on the underside of the seat), has been changed. Im a little afraid to remove that underside to see if there is possibly still an original tag inside the seat, so I thought I would come to you guys and ask some advice or best way to confidently say these are indeed what they are supposed to be. I truly believe they are, because the gentleman I purchased them from is a respectable and trust worthy person, but in selling them, its what the customer believes that is important. In addition, if these are authentic, what are they worth? Pictures to follow.