I'm installing (1st timer, do-it yourself) marble tiles (12' x 12") on a corner fireplace surround and hearth. The backer board is installed per recommended procedure. I am planning on using metal Schluter Rondec for the corner of the facade and the front edges of the hearth (the marble tiles are not available in bullnose). The color of the Rondec closely matches the marble. Looking through examples of model marble fireplace installations, I don't see projects that use Rondec. Is the use of Rondec or other such products "tacky" and characteristic of an amateur installation?

I would not say tacky but maybe industrial. What is the rest of the floor in front of the hearth? I would prefer a nice Oak trim transition.

Sometimes, there isn't much of an option. Maybe running some sort of casing up the sides will eliminate some of what you need to do. If using Rondec, you could match the metal of your fireplace, be it brass, powder coated black aluminum, etc. There's what, like 20 or so finishes available in Rondec? Don't cheap out if using rondec and miter the corners. Spend the extra bucks for the preformed corner pieces. Not only will it look more professional, all your rondec cuts will be straight so there's no playing with miters and ending up with a slight gap between mitered pieces. I'll post some pics today of the field honing I'm doing on some custom shower shelves and maybe that will be enough to give you an idea how to polish the sides yourself and you could do it yourself, or you could contact a few local tile installers and see if they can shape and polish them for you. Sometimes a tile store might offer the service, call around to them. Another place to try would be any local place that sells and makes grave markers. They spend all day grinding, etching, engraving and polishing stone and do it so well, folks die for their services. ;):D

Where are you located?

Thanks to Bljack and to ballengerb1 for the responses. I don't seem to be able to send a message to either directly so am posting this message to say thanks. ballengerb1: The hearth is elevated, so I am talking about a 90 degree tile corner rather than a hearth deck that extends on the floor out from the fireplace, where I could use a piece of oak to trim it. Bljack: yes, polishing the edges of the marble pieces that would show has occurred to me. I would like to see photos of your project.

Thanks to you both.

I agree with bljack and the polishing... I personally am not a fan of using any kind of metal trim along side marble and stone. Oak always looks great along side marble however and it's quite durable compared to other types of trim.
Be sure to use hard plastic spacers when you install marble you want the joints to be tight.

Good luck.