I got an email which had the above picture attached. The owner said,

"I have shown this item to a reputable collector of fire grenades. His emphatic opinion was that this is not a grenade of any kind. I've been told everything from it being a sock darner to a dresser bottle and everything else in between."

Dimensions:

"Roughly 5" tall, 3 1/4" in diameter at the globe and 1 1/4" in diameter at the stem."

The owner says the groove at the bottom led him to contact me as he thought maybe this indicated it to be some sort of insulator. Any ideas?

Thanks for the help - general consensus is a lawn ornament called a gazing globe.