There are other decorative elements common to most mosques. For instance, a large calligraphic frieze or a cartouche with a prominent inscription often appears above the mihrab. In most cases the calligraphic inscriptions are quotations from the Qur’an, and often include the date of the building's dedication and the name of the patron. Another important feature of mosque decoration are hanging lamps, also visible in the photograph of the Sultan Hasan mosque. Light is an essential feature for mosques, since the first and last daily prayers occur before the sun rises and after the sun sets. Before electricity, mosques were illuminated with oil lamps. Hundreds of such lamps hung inside a mosque would create a glittering spectacle, with soft light emanating from each, highlighting the calligraphy and other decorations on the lamps’ surfaces. Although not a permanent part of a mosque building, lamps, along with other furnishings like carpets, formed a significant—though ephemeral—aspect of mosque architecture.