**Table 2.**

We used both carbon and noncarbon fillers. All the fillers were crushed to the size of particles passing through a sieve with a size of 0.5–0.2 mm holes. **Table 2** gives an overview of the filler characteristics. These are pitch coke (PC), shale cokes (SC), and shale coke after heat treatment (SC-T), which we preheated for 2 hours at a temperature of 250°C to remove moisture. For comparison, we took hardened glass, washed bank-run sand, and anthracite.
