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Collectibles--General (Modern)/dominion glass insulator


Hi there I have been trying to find the value of my glass insulator.  It is a dominion-42. It has a d inside of a diamond with a faint 50 beside it and a faint 5 below it. I say faint because it is not as prominent as the 42. If you could help out that would be great!
the very best, Jen

Thanks for your question -- We identify your Dominion-42 as a CD 154.  The CD numbering system was developed by collectors to identify the various styles.  This is a Canadian made insulator that can be found in a number of colors.  The faint "50" is the mold number.  This is a pretty common insulator if the color is clear.  If it is amber or a very attractive blue color it could be better -- if there is a question on color, please send a picture.

In clear these are common with a $1.00 or so value.  Still a great piece if history!

         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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