Am Tel Question

Editor's note: A collector who wishes to be called "The Rhino" has agreed to answer questions sent in by readers. The Rhino will address general questions about insulators and the hobby. N.R. Woodward, affectionately know as "Woody", has agreed to continue answering reader questions, too. Woody is the creator of the Consolidated Design system of classifying insulators based on their shape. On behalf of readers, Crown Jewels will submit questions related to why certain insulators have certain CD designations to Woody for his answer.
                                                                 

Question: "I'm looking for help in identifying my glass insulator. It has "Am Tel & Tel Co" and a "3" on the dome, but no other type on it. It is aqua in color. Can you help me?"

Rhino's Answer: The American Telephone and Telegraph Company had several glass manufacturers produce insulators with the company's name on them. The embossing may be lettered "Am Tel & Tel Co" or "AT & T Co". Insulator styles include CD 106, 121, 160.6, 190/191, 192/193, 192.1/193.1.

Without a picture to go on, it is likely that your insulator is a CD 121 based on your description that the embossing is "on the dome". None of the other CD styles have the Am Tel & Tel name above the wire groove. But one early style of CD 121 tolls has the Am Tel & Tel embossing on the crown above the wire groove rather than on the skirt. The name is on one side of the crown, while a number is found on the opposite side. In between, look for a mold line that extends over the top of the dome. A mold line over the dome (MLOD) indicates that the insulator was made in an older style two-part mold. Aqua is a common color. McDougald's price guide identifies this embossing style as (020), and values the insulator in aqua at $10 to $15. It's rarer in green glass, and would be valued at $100 - $125 in that color.

What's the rarest insulator made for American Telephone and Telegraph? Both the CD 160.6 "baby signal" in yellow green and the CD 192.1 / 193.1 are priced at $2,000 to $2,500. But examples do show up at shows and internet sales locations from time to time. Rarely encountered, however, is the CD 106, an ordinary looking pony in aqua with sharp drip points. It's also valued at $2,000 to $2,500.

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