Historically, glaciofluvial materials deposited during the ice age have provided a good source of concrete aggregate in Sweden. These natural aggregates are of rounded shape and quite favourable grading. Nevertheless, alternative sources of aggregate are now considered due to environmental reasons and to preserve the remaining eskers. Crushed rock presents a good replacement for the concrete industry. However, it is important to adjust the mix design of the concrete accordingly to the new properties of the material. Most rock in Sweden is granite, showing a large variation in the properties of the crushed fines. This variation needs to be studied and classified since many of the fresh and hard concrete properties are dependent on the fines. According to , three main factors that affect the flow properties of fresh concrete are particle shape, friction and interlocking.