Aggregate Map for USA and Canada

    SOFT

    Soft Limestone
    Sandstone
    Dolomite Limestone
    Sillcodus
    Soft Shell

    MEDIUM SOFT

    Pit Gravel
    Limestone
    Dolomite

    MEDIUM

    River Rock
    Medium Taprock
    Decomposed Granite
    Medium Crushed Gravel

    MEDIUM HARD

    Granite
    Slate
    Taprock
    Basalt
    Quartzite

    HARD

    Hard Chort
    Quartz
    Flint Rock
    Hard River Rock

    These are the basic aggregates found in shown areas
    Other types of aggregate can be found in many parts of the US and Canada

    There are many different types of rock used as aggregate. Generally, hard aggregate breaks down the cutting diamonds faster which means the bond must be softer to expose new diamonds. Softer aggregate generally does not break down the cutting diamond as quickly and therefore requires a harder bond to hold the diamonds in place to use their full potential.