## 3 Results and Discussion
### Morphology
Additionally, a considerably higher decrease in angularity after the micro-Deval test (when compared to the Los Angeles test) was found. This can again be explained by the absence of breakage. Absolute shape parameters' values in relation to mass loss in general indicate a faster approach to smooth round shapes for particles abraded in the micro-Deval apparatus--low-energy abrasion. A general increase in roundness and smoothness of abraded particles was observed by [PERSON] et al. [46], [PERSON] and [PERSON] [50], [PERSON] et al. [51], and [PERSON] et al. [52]. Figures 14-16 show a relative change of shape parameters in relation to input energy and mass loss, as well as an absolute value change. Morphological parameter data obtained from low-energy abrasion tests in the micro-Deval apparatus are marked blue, while the data obtained from high-energy abrasion in the Los Angeles machine are marked orange. The considerable differences in the morphological evolution of particles resulting from different energy levels in experimental abrasion indicate the possibility of using particle morphology to identify the transportation conditions they have experienced. Figure 14: Sphericity changes of abraded material. Data for micro-Deval abrasion tests are marked blue and data for Los Angeles tests are marked orange—(**a**) relation between input energy and sphericity change; (**b**) relation between cumulative mass loss and sphericity change; (**c**) relation between input energy and sphericity value; (**d**) relation between cumulative mass loss and sphericity value. The absolute angularity value after the first cycle of abrasion in the Los Angeles machine dropped for coarser particles, but the angularity of newly produced (by breakage) particles was higher than that of initial particles. On the other hand, particles in coarser size classes experienced a lowering of angularity. This can be interpreted as an indication of the presence of a higher angularity value. Figure 16: Convexity changes of abraded material. Data for micro-Deval abrasion tests are marked blue and data for Los Angeles tests are marked orange—(**a**) relation between input energy and convexity change; (**b**) relation between cumulative mass loss and convexity change; (**c**) relation between input energy and convexity value; (**d**) relation between cumulative mass loss and convexity value. Figure 15: Angularity changes of abraded material. Data for micro-Deval abrasion tests are marked blue and data for Los Angeles tests are marked orange—(**a**) relation between input energy and angularity change; (**b**) relation between cumulative mass loss and angularity change; (**c**) relation between input energy and angularity value; (**d**) relation between cumulative mass loss and angularity value. that large particles, as they approach roundness, lose parts that become more angular. With further abrasion, all of the particles experienced a lowering of angularity, with coarser particles being more angular than finer ones in each cycle (Figure 17). This observation is applied only to those particles that were investigated for morphological changes (i.e., coarser than the 20 mm sieve).