I have recently aquired several glass insulators and I am trying to ID them and evaluate their value. I have Id'd one as Hemmingray 121, with Am Tel & Tel Co embossed on it. Does it change the value because of the embossing?
I can't comment but I did find this cool site. http://www.hemingray.info/index.htmlI never knew about that one but I don't collect insulators so I never looked for it before either.
The insulator is embossed with both Hemingray and AM Tel & Tel CO.? I don't have the 2011 guide in front of me but prices on these tolls (the CD 121 style is referred to as a "toll") as well as most CD styles mainly depends on color and not embossing variation. Dome embossed AM. tolls fetch a bit more. This appears to be a complete list? of EIN's (embossing index numbers)http://www.hemingray.info/database/detail.php?cd=121 . I see Hemi 121's with AM. Tel blotted out.
The prismatic embossing of AM. TEL. & TEL. is attributed to Hemingray manufacture, and occasionally comes in the flagship Hemingray blue color. There is a similar CD121 prismatic embossed Hemingray / Patent May 2, 1893.
If it is prismatic and indeed Hemingray made Am. Tel. & Tel., they may fetch around $10, sometimes more if there is a decent amount of bubbles or fizz in Hemi blue.
There are tons of Am. Tel. & Tel. and AT&T molds, so the embossing is nearly irrelevant. The better ones have a mold line over the dome, or embossed on the side of the dome, or in colors other than aqua (except when there is junk or streaks in the glass).
If you have pics of your insulators, we can definitely help better.