A prominent keystone variant, designed to cap a 2.5-meter arch, is a robust, central wedge-shaped block of sandstone. Its form is more dramatically tapered than a regular voussoir, with its widest face intended for the arch's apex. The stone is a rich, earthy ochre, exhibiting a coarse, granular texture. Similar to its companion segments, its edges are significantly worn and rounded, lending it a weathered and ancient tactile quality.

A prominent keystone variant, designed to cap a 2.5-meter arch, is a robust, central wedge-shaped block of sandstone. Its form is more dramatically tapered than a regular voussoir, with its widest face intended for the arch's apex. The stone is a rich, earthy ochre, exhibiting a coarse, granular texture. Similar to its companion segments, its edges are significantly worn and rounded, lending it a weathered and ancient tactile quality.

A prominent keystone variant, designed to cap a 2.5-meter arch, is a robust, central wedge-shaped block of sandstone. Its form is dramatically tapered, with its widest face intended for the arch's apex. The stone is a rich, earthy ochre, exhibiting a coarse, granular texture. Its edges are significantly worn and rounded, lending it a weathered and ancient tactile quality, perfectly fitting its role as a sturdy, central architectural element.