Very Rare Pair of Antique Chimney Pots fleur de lys

Offered for sale is this very rare pair antique chimney pots. The pots were part of my late fathers collection. His most prized pots. I have never seen anything to match them on the market over the last 20 years and they must have come from a very important/grand building or estate. Fleur de lys emblems to all sides of the pots. The pots have signs sings of weathering and natural erosion of the material they are made from. Some minor nibbles, one large chip as photod