These were made from two longer pillars of red Egyptian porphyry, recovered in the 11th century and sawn in half.
The mihrab is made of veined white marble, red porphyry and green diorite.
The lower part of the pedestal is of dark gray granite and red porphyry.
The upper part of the pedestal is made of red porphyry.
The rectangular niche facing the entrance most likely contained the sarcophagus of Helena, in red porphyry.
The main door is framed with a simple mosaic of red and green porphyry.
Her hair looked as dark as red porphyry in the glimmer of daybreak.
A ten feet high screen of red porphyry surrounds them.
It is surrounded by small scalloped arches of red porphyry.
They created beautiful marble floors with mosacis, often with inlays of green and red porphyry.