US Aggregate Map & Mohs Hardness Ratings

Aggregate Map of the US

Mohs Hardness* Aggregate Used in Concrete Mix
8
Very Hard Aggregate (Flint, Chert)
7
Hard Aggregate (Quarts, Hard Gravels)
6
Medium Hard Aggregate (Medium Gravels, Granites)
5
Medium/Soft Aggregate (Soft Granite, Dolomite)
4,3
Soft, Abrasive Aggregate Limestone