Hi Kalleroonian
Not sure how interesting/useful you or anyone else will find this, but I'm also taking time to choose ballast I'm 100% happy with. The 'model shop' varieties really don't appeal to me. I prefer that lovely, natural medium... sand. I'm lucky enough to live near seaside and riverbank supplies a golden mix from the beach and a browny one from the river (Dart). I prefer sand because it's so variable (and I do mean full of variety), both in colour and size, quite unlike the purchased examples. It's also inexpensive!!
I sieve off anything larger than just under a mm in size, which means I'm left with grains that scale to no more 2.5 inches. I used to discard the really small stuff (see pic in post 6 above), but now keep most of it and only throw the really really tiny specs.
The first photo below is of the ballast at the north (or so called east) of Newton Abbot station, showing the appearance I'm wanting to near-enough create.
This second photo shows a test piece using my original mix of sea and river sand, which is quite light in colour (and not unlike a great deal of ballast around these parts).
The last two photos show my first attempt at achieving the Newton Abbot colour having treated a spoonful of my original mix with Modelmates Sand Brown Weathering Liquid. Misted water on the sand first, then added a few drops of the Liquid, then gave it a good ol' mix before leaving in the sun to dry.
The result makes me think I'll be adopting this pre-colouring approach to all my ballast, making use of other colours from the range as required. Slate Grey came out nice but Soot Black will probably be very useful. Spot colouring with Oil Brown (after ballasting) might have potential where locos stop and do their business! But first I need to find out what effect the gluing process (using Copydex) has, if any.
Cheers