The following link will tell you all about them.
Then I tried to think of some examples of modern metal lace but the only one of I could think of was the Australian Coat of Arms that sits above the main entrance to Parliament House in Canberra. It is made from stainless steel and made specifically for the building which opened in 1988. You can see a photo of the Coat of Arms at http://members.virtualtourist.com/m/p/m/1f3675/
It seems ironic, when comparing the metal structure on the a traditional building in Paris with the metal structure on a modern building in Australia, the Australian metal lace has a traditional feel while that of the traditional building in Paris has a modern feel to it.