View more images

If you're looking for keystones for your home, hotel, or restaurant, don't settle for second best. Work with Stromberg instead. As the world's largest producer of keystones, we can offer you unsurpassed selection and the best quality and service in the industry. We can also craft one of a kind custom keystones just for you.

Capacity and Experience

  • Three decades experience serving world's finest resorts, casinos, shops, and restaurants
  • A history of completing large and complex jobs
  • The world's largest factory of its kind
  • The materials, professionals, and experience to deliver world class performance


  • Complimentary initial estimates and consultations
  • CAD drawings
  • Models and maquettes
  • Production
  • Installation upon request


  • Glass Fiber Reinforced Polymer (Fiberglass)
  • Glass Fiber Reinforced Concrete
  • Glass Fiber Reinforced Stone
  • Cast stone

Keystones overview

A common architectural feature of medieval structures, keystones found years ago on buildings provided vital structural support. Found above windows and doors, keystones were placed at the highest points of arches, where they served to secure all of the arch components.

While keystones are no longer a vital part of the structure of most buildings, they are popular decorative features that can greatly improve a building's façade. Stromberg's decorative keystones can be placed above most types of windows and doors. We can match the color of your window surround if you just want to add a subtle touch, or we can craft keystones that will serve as stunning focal points. Several of the materials we use to craft our keystones are very lightweight, so installing them is quick and easy. You won't have to worry about installing extra supports, or whether the keystones will place excessive stress on your doors, windows, or surrounds. Our keystones won't wear away, crack, or rot over time like many other materials, so you will likely never have to worry about repairing or replacing them. Contact us today to find out how this medieval element can complement your contemporary structure.