COPENHAGEN — Early on Tuesday morning, the Børsen, Copenhagen’s stock exchange, caught fire, reminding many in the city and spectators online of the 2019 Notre Dame fire in Paris. The two buildings have some key features in common, namely their age. The Børsen, constructed between 1619 and 1640, is newer than the French cathedral, but because of its age, reconstructing the building presents unique challenges. The materials used to build the Børsen are difficult to come by four hundred years after its initial construction. One of the building’s most affected parts is its iconic spire… made from intertwining four dragon tails, collapsed. While the building is made of red brick, the spire, which stands at 140 feet, features three golden crowns above the tails, representing the short-lived union of Denmark, Norway, and Sweden. …The exact material used to build the spire is unknown, but many speculate that like Notre Dame, it was carved from wood and coated in lead.