10 Hectares/25 AcresIf these truly are Kimberlite pipes (Which i beleive they are), they truly are monsters. The next question is if they are diamondiferous and if they are, are they economical?
Saskatchewan has some large pipes (ie: sgf, Shoregold) however grades are in question as to wether economical or not and need serious money spent (I think 2Billion?) to prove them up/build a mine.