The Stone Boulder Wall is a building-block looking like it was put together by rounded grey boulders on all 6 sides.
It can be crafted in your Crafting Menu (default key "q") after the according crafting recipe has been unlocked by
To craft 8 (blocks of) Stone Boulder Walls at a time, you'll need (as of R44 in June 2017):
- 2 Stone, which can be mined from the Fossil layer in Caves or from Mountains, hillsides or recesses near rivers without requiring any Power Cells to be equipped
- 1 Stone Rod made of Stone, Limestone or Bedrock in a Processor
- 1x Melted Wax made of Beeswax in a Forge or looted from Wood Treasure Chests or Stone Treasure Chests