The type of materials you choose will dictate the style of the room
Think carefully about the materials you want to use, for the mantel, hearth and chimney-breast cladding. For natural stone mantels try Templestone . Their masons renovate cathedrals, and the fire surrounds and hearths they make, including one made from Italian black slate, honed to produce a gorgeous satin finish, are produced by hand in Somerset. Montpellier Marble specialise in travertine and marble.
For a contemporary haven, contact The Platonic Fireplace Company who make the very sleekest in town, as they work with some of the UK’s leading architects, and they are experienced in trickier bespoke designs. For cast iron, original pieces go to The Antique Fireplace Company or Agnews for reproduction ones. Then brushed stainless steel (although fairly industrial), is a great way to bounce light around a room when the fire is burning (panels start at about £140).