About 6 months ago, some of my relatives were visiting their hometown in Poland. Somewhere in the process of getting there, vacationing a bit, and then heading home, they came across 3 Polish insulators. I was incredibly surprised and pleased to receive 2 of these when they returned home! (the third broke while making the trip in their baggage). The piece on the left is a white porcelain piece with two wire grooves, and is stamped "C2003" and under that, "N80/2" on the dome. It can be assumed that "2003" is the date of manufacture, so it is not terribly old. The piece on the right, however, is a different story! I'm intrigued! It's probably not old, but it is a beautiful and small thing of beautiful clear glass, and it came from the country of my ethnicity!
The embossing runs around the crown of the insulator, and it reads, to the best of my Polish interpreting abilities: "CENA 210 IŁ Ns 80" The "A" in "CENA", however, is upside down for some reason. The insulator is a beautiful sage green colour, and is 3" tall, by 3 1/8" wide.
Mr Edward Brown has helped me to conclude that the insulator on the right is a CD 472. The "80" embossing on the crown is a measurement for the diameter of the skirt in millimetres, and the piece probably dates from the 1930s to the 1970s
UPDATE: Rick Soller has dug up some additional information on the embossing on the CENA piece, suggesting that perhaps the marking corresponds to pricing, not diametre:
"Although the diameter of the CD 472 is 80 centimeters, I have also heard from a collector in Poland that this embossing was used during Soviet occupation of the country and, to keep black market activities down, the price of the insulator was embossed on the insulator. Another definition of "CENA," besides "dimension" is that CENA means "price" according to Google Translate. Adding to the argument that "price" is the correct translation, some CD 472s are embossed CENA 10 or CENA 2 40. I'll post the question on the European insulator Facebook page to get a final ruling."
This information was confirmed via Polish collector, Dominik Kałużny, in the "European Insulator Collectors" Facebook group.