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Collectibles--General (Modern)/CD 121 Early Prismatic Style



I purchased this at a flea market this weekend and tried to do some research on line about it.  As I read I found out that some read A.M. TEL. & TEL. COM. or they will have no dots at all.
Mine reads A.M. TEL & TEL. COM. no "." after the first "TEL"  Thanks for your help.
Pictures are attached.

Hi and thanks for your question,

These CD 121 Am. Tel. & Tel. Co. styles were made by a number of different glass works as well as in large volume.  A.T.& T.Co. was trying to standardize insulator designs so they could get consistent results from different glass works. There are a huge number of variations in punctuation with periods and no periods.  The price guide does not cover all the variations.  A collector could have a lot of fun trying to locate all the different markings and mold variations in these.  I suspect yours is a Brookfield product.  I don't think the various differences in periods makes a value difference, but clearly it designates a different mold.  

         Hope this helps,   Thanks, --Bob

Collectibles--General (Modern)

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Bob Berry


Questions related to collecting Glass Insulators and porcelain insulators - I can provide historical information as well as current collector values. I am also interested in purchasing insulators I need for my collection.


I have collected since the early 1970's and have much historical information, as well as knowledge of current insulator values.

National Insulator Association (

BS & MS in Electrical Engineering

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