Question: In which city is this American luxury jewelry and specialty retailer anchored at the signature landmark plaza in Frontenac, Missouri, along with Saks Fifth Avenue, Neiman Marcus, etc.?
Sentence (from "Tiffany &amp; Co."): Tiffany & Company (known colloquially as Tiffany or Tiffany's) is an American luxury jewelry and specialty retailer, headquartered in New York City.
Relevant evidence: Yes