Grouting Travertine Tile
Should the travertine tiles be sealed before grouting?
You could seal your travertine tile before grouting, especially if it's a flat honed finish, but really I don't think it's absolutely necessary.
Travertine is pretty dense and doesn't absorb a lot, so you may not need to seal.
I would test your travertine first by putting some water on it to test it's absorbancy.
If you feel it's absorbing quite a bit of water, then maybe you should seal it.
Remember you're trying to prevent any staining problems from grouting your travertine tile.
Testing is key to your question. Usually travertine is very dense, but the only way to truly know is to do a test.
I hope this helps.