Here is another suggestion for your cobbles, which I'm using in a dio. at the moment.
Get up in the loft and find some polystyrene packings that the t.v., whatever, came in.
Make sure it's the hard, compact type. (You will see the beads/cobbles in the stuff)
Cut it to the thickness required, but don't cut the flat, top surface, this will ruin the cobbles. Cut the underside..... Then just paint it blue/grey and add some dust, job done! It's quick and easy to do and might be just the ticket for the large area you are doing.
I hope you don't mind, and I know it's bad form to post a picture on someone else's thread, but it's probably better than trying to explain how it can turn out!
I hope this is of some help in you quest and good luck with the build.
Any chance of some progress pickies?
Cheers,
Ron
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