For those wondering about my methodology for these chunk count figures, here's what I did : I stripped all my mods, went into a rich explorer run and landed in a big plain. I then covered the map in one big dump stockpile, went into caravan formation and counted the chunks. Then I moved my pawn to another nearby hex and settled there, repeating the method until I had enough data. Here are the results :
650/650 900/800 700/800 860/830 858/725 820/950 830/750
520/475/438 460/450/450 590/530/500 500/600/400 510/550/400
Used some broad language therefore. I don't think it needs to be super scientific but I feel like it can be a useful ballpark number for anyone who plans on using a lot of stone.