In 2014, a long-lost piece of the Dutch city of Leiden was recovered. The remains of a medieval bell tower - the core of the old city - were found in the basement of a perfectly ordinary jewelry store.
When jewelry purveyor Rob van Gerner bought the Art Nouveau building on the corner of the Breestraat and Maarsmansteeg, development was held up due to the presence of an old wall in the basement. After six months of negotiations with local authorities and archaeologists, Gerner got permission to remove it, only to find an even older wall behind it.
This older wall is a remnant of the first bell tower of Leiden, which was commissioned by Willem II, Count of Holland, in the 14th century. The tower was connected to the count’s Leiden residence and rung in the case of fire and other hazards. The crumbling stone blocks were successfully identified thanks to the tower’s depiction on old blueprints and sketches, where it marked the city’s center for hundreds of years. (Right in front of the building is the Blue Leiden Stone, the city's old central justice point.) The wall was also identified thanks to its giveaway thickness - the stones were laid two abreast to be nearly 80 cm in depth. According to medieval law, only noblemen were allowed to build with such heavy, protective masonry.
The bell tower eventually became obsolete and was mostly cleared to make room for new buildings. This is all that now remains. And although these stones may not sparkle like the ones in the shop upstairs, they are precious stones indeed.