I've used a masonry blade on cultured marble.
I put masking tape on the bottom of the saw guide so I don't scratch the marble.
Marble is pretty soft, but can I cut it OK dry using a fine-tooth carbide blade on my circular saw? I need a nice edge so no chipping would be best. Any detailed help appreciated. Thanks.
Carbide will cut it, but since there is no way to know the stone's structure (minor fissures, cracks, weak points, etc.), cutting it with that type of blade is chancy. A wetsaw is less likely to chip the edges, but even that is no guarantee. Felker makes a small wetsaw that looks like a circular saw (better quality for about the same price as the one available at the big box stores). Needless to say, you'd want to use it outdoors, since it will be spraying water everywhere, but it's pretty flexible in what it will cut.
A typical wetsaw blade is a continuous rim, diamond embedded steel. It acts more like sandpaper than a saw and is less likely to chip out things, but it can still happen.
Cutting this stuff dry would raise a huge dust cloud and heat up the blade quickly.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014