The first element is the type of fire itself.
The consideration of wood or gas is most relevant at the final stage – the lighting of the fire. With an actual wood fire you will never lack the sound of a wood fire crackling and glow of real embers. The alternative is a gas insert. There are many new and different designs for gas flames as well models of inserts themselves.
The second element for consideration is the facing on the structure.
This is where there are the most trends, even regionally. Traditionally, brick has been the first choice among homeowners. With the advent of manufactured stone, the cost and availability has made it a popular choice. A coat of stucco has always been popular in the southwest regions. We even see a modern trend of poured concrete or even fabricated metals in very contemporary structures.
The third element is choice of mantle.
This is where the fun really starts. How much mixing and matching are you comfortable with? Something to keep in mind is balance and proportion. Mixing materials and even styles is smart and sexy, just make sure your mantle doesn’t outweigh your fireplace or the opposite.