It will be best to use a continuos rim blade suitable for marble. Always use the right blade for the right job. If you are not going to have any edges showing you can use a dry cutting blade (for marble) but depending the type of cutting, the vibrations through using a angle grinder will chip the edges or in some situation break the stone.
If is a one off job, I personally recommend you hire a decent wet cutter (with the barble blade) with the widest trays to support the 600 width span. If on the other hand you are going to do more of stone work, then it will make sense in purchasing a decent wet saw. I use a Ruby and it is good starting point.
Hope this help.
