Yea I've never seen it, looks 1910's-to early 20's. I can't on the paper site as my subscription ran out. There are a few guys I know that I can ask.
Saskatchewan used these bottle styles as...
Well that's an interesting item!...thanks for sharing.
So what is it made of?
Heres a cleaned bottle. LEON.
Found a Skull with some big Fangs under there. LEON.
Very cool! Yeah that spot definitely looks like it warrants some further investigation. No telling what could be buried in there.
Unfortunately there are no markings on mine, so we'll probably never know. It sure does look like those transitional bottle you have though.
Your whiskey appears to be European, I think. I've got a German beer with a similar top, never seen anything like that from North America.