The feeling of religious conservatism which has preserved the structural rudeness of the Ka'ba did not prohibit costly surface decoration. In Mahomet's time the outer walls were covered by a veil (or _kiswa_) of striped Yemen cloth. The caliphs substituted a covering of figured brocade, and the Egyptian government still sends with each pilgrim caravan from Cairo a new kiswa of black brocade, adorned with a broad band embroidered with golden inscriptions from the Koran, as well as a richer curtain for the door.[18] The door of two leaves, with its posts and lintel, is of silver gilt. The interior of the Ka'ba is now opened but a few times every year for the general public, which ascends by the portable staircase brought forward for the purpose. Foreigners can obtain admission at any time for a special fee. The modern descriptions, from observations made under difficulties, are not very complete. Little change, however, seems to have been made since the time of Ibn Jubair, who describes the floor and walls as overlaid with richly variegated marbles, and the upper half of the walls as plated with silver thickly gilt, while the roof was veiled with coloured silk. Modern writers describe the place as windowless, but Ibn Jubair mentions five windows of rich stained glass from Irak. Between the three pillars of teak hung thirteen silver lamps. A chest in the corner to the left of one entering contained Korans, and at the Irak corner a space was cut off enclosing the stair that leads to the roof. The door to this stair (called the door of mercy--Bab el-Rahma) was plated with silver by the caliph Motawakkil. Here, in the time of Ibn Jubair, the _Maqam_ or standing stone of Abraham was usually placed for better security, but brought out on great occasions.[19]