Appears to be a very small chip or indent on rim of the chimney as shown in pics The KLM Blue Delft BOLS Miniature House #7 is a collectible bottle from the Netherlands, featuring a design inspired by the iconic KLM airline. This miniature house, or bolle, reflects the history and cultural significance of Dutch aviation. With its intricate details and national pride, this empty 2017 edition is a unique piece for aviation enthusiasts and collectors alike.
eBay