Either option is acceptable.
Corner Stone is the album by Holly Dunn
The sacrum is sometimes known as the "cornerstone" of the pelvis
1. Cover the outside receiver 2. blitz 3. protect against the run 4. help other d-backs with coverage
Newer castles were made with stone and rounded corners. the reason was that it was an advance round corners were good because they had fewer space to hide and also the shape deflected any catapults...