Ballast

Long time no update, I know. I've had a lot of other things going on and haven't spent much time in the basement over the summer. This weekend I've hit it in force though. Trackwork is in place for the new (west) yard and soon I'll be tackling the rest of the mainlines and getting trains rolling. I've been thinking about what I want to use for ballast. The most common commercial products are too coarse (even their "fine" version). I happened to be near a craft store yesterday so I stopped and picked up some colored sand. Sadly, there was no light gray... but I think with suitable weathering, the white sand may work well. What do you think?

It's a little sloppy, I just threw this together to test the sand texture and color as ballast. Black for (cinder ballast) in the yard, white (limestone?) for the mainlines. Any thoughts or suggestions?