Collectibles--General (Modern)/Brookfield Insulator.


Hi Bob, thank you in advance for your time. We were recently given a box of old stuff from a neighbor which happened to include a couple of glass insulators. I did some research online and read an interesting piece on Brookfield insulators and it appears this one could've been made between 1880-90 which is exciting since it would be the oldest item I have owned.

Anyway, it only has the name and addtress on one side "W. Brookfield 45 Cliff St. N.Y." It also has some type of stamp on top....looks like a larger backwards 7 with a smaller standard 7 at the bottom of the larger 7 forming an "x" as the two cross.

It does appear to have an inner skirt but up further inside the outer skirt. Threaded inside of course and color has hints of blue but when held up to an incandescent light appears to be an aqua green?? Seems like it could be a CD145??

Ok thats it...any more history for me and how about a value? just a neat paper weight I suppose haha

Thanks for your question and sorry for the delay.  It looks like you have done some good investigation on your own to start.  I do suspect this is a CD 145 "beehive" style.  The numbers or letters on the dome are for production tracking.  For the 45 Cliff Street address you are right about the manufacturing dates, making this insulator at least 120 years old!  Aqua is the most common color for this piece and although very old they are pretty common.  These usually have a $2-$4 value in aqua.  This piece can be found in good shades of green as well as purple which are worth significantly more.  

For sure a great piece of history made by the Brookfield Glass Company (William Brookfield was the president at the time).  They made insulators from about 1863 to 1922 and were initially based out of Brooklyn, NY and then in the 1890's moved to Old Bridge, NJ.

         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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