@mowingman posted:Joe,
The dust will not be an issue after it is glued down, as you mentioned. It will be very nasty and quite evident while placing and spreading the limestone ballast. Very similar to people's experiences using dusty cat litter.
Jeff
The dust might be a problem because it could change color once it is glued down. I used crushed stone for ballasting a test track and didn't wash it first, and all the dust mixed with the glue solution and dried a much lighter color than the actual rock.