Mining stonecutter gives different looking items based on direction

Steps to reproduce:

1. Place a stonecutter facing north/south and another one facing east/west;
2. Place a chest nearby;
3. Mine one of the stonecutters and store it in the chest;
4. Mine the other one and compare both item icons.

Expected results:
Both of them look the same.

Observed results:
Although they're still the same item and can be stacked, they are facing different directions when they're in separate slots. See attached picture.