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Collectibles--General (Modern)/Help identifying insulator


QUESTION: Hello Mr. Berry. I found an insulator today along the railbed of an old/abandoned trolley line in Cranberry Township PA (Info about the line here:,_Harmony,_Butler_and_New_Castle_Railway). From what I can see on the Internet, this would seem to match a CD 145 Grand Canyon (Beehive) insulator. It has no markings on it and I think the color is called "aqua"(?). As the trolley line was built in the early 1900's I would assume that this is approx. 100 years old (assuming it was in fact associated with the line.) It seems to be in reasonably good condition, but it has a lot of flaws - bubbles, surface cracks, that seem to be as manufactured. Any information you could provide regarding age, maufacturer, and application, etc. would be appreciated. Thanks for you interest! Sincerely, Bob

ANSWER: Hi Bob --

This does not look like a Grand Canyon style but more like a Brookfield.  Can you look very closely and make sure there is not a "B" on the skirt?  These Brookfield styles would fit the Pennsylvania location and match the appearance of the insulator you found.  Grand Canyon styles were made by the Western Glass Manufacturing Company of Colorado and are almost never found East of the Mississippi.  Let me know if you confirm there is no "B" on the skirt.

         Thanks, -Bob

---------- FOLLOW-UP ----------

Insulator showing \'B\'
Insulator showing 'B'  
QUESTION: OK Mr. Berry, I took another look... There is in fact a "B" present. It is very slight and I felt something before I actually saw it. Attached is another picture. The B can be seen in the enlarged portion of the picture on the right. The B is approx. 1/4 inch tall. The insulator has two slight vertical mold lines 180 degrees apart and the B is centered between them (at, say, 90 degrees) just below the wire groove. There also appears to be another mark at 270 degrees - or opposite the B. It is a short vertical line - maybe the number "1"? It is the same size of 1/4 inch. So Brookfield it is? Do you have  any idea of its age or use? I would assume telegraph, telephone, or some other low voltage application? Thanks for your time and quick response! Have a great Easter. Bob.

Yes this is typical of these.  Sometimes the B is hard to read as the molds were used for a while.  These data from the 1890s until shortly after the turn of the century.  Brookfield was transitioning from Brooklyn, NY to Old Bridge, NJ at this time.  They remained in business until shortly after WWI in 1922.  These were telegraph and telephone use.  They are pretty common as many survived -- still a great piece of history!

         Thanks, --Bob

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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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