I'm trying to find out if anyone can identify this marking, which MIGHT be on a portion of an insulator. it was found among other glass items during an archaeological project. The mark appears on what MAY be an insulator dome shard that was knapped (for a scraper or Indian tool), and is possibly a shop number on a Brookfield insulator(??) If anyone can Definitely identify this marking (or if they have seen it on a bottle or another type of glass) or can ID it as a shop number they have persnonally seen on an insulator, can you please email me at davidrussell59@att.net ? Thanks!!

Update: (11/22/2017) thanks for all the input. It is almost certainly the dome portion of a CD 145 "B" beehive, with a 1 (double stamped) backward 4 shop number on top. I haven't found an *exact* mold duplicate (yet), but several collectors have sent me pics of similar numbers seen on that type of insulator. A shop number that looks very similar appears on a B beehive and a pic of that piece was kindly sent to me by Mary Ann Pike.... her picture is here: [id=515948907].