Love to try and help you out bud, but either I've never heard of CR 610 Limestone or your question is a little vague. Do you have a few more details regarding your inquest (ie proposed application, site details, location, construction usage, etc).
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora. See faq158-922 for recommendations regarding the question, "How Do You Evaluate Fill Settlement Beneath Structures?"
610 is a local spec (not an astm specification) for the south/southeastern united states. i have recently run across the "standard" gradation for this material and can provide it to you should you need it. Thanks for the responses.
civilmg is right. 610 is a commonly specified dense-graded crushed aggregate in the Southeast. From a gradation standpoint it usually runs from 3/4 inch to dust, and maximum dry density for a limestone or dolomite derived aggregate is on the order of 140 pcf.
![[pacman]](/data/assets/smilies/pacman.gif "[pacman] [pacman]")