In order to lighten the apparent weight of the dome it must be covered with patterns and colours so as to deceive the eye and the mind and to suspend them from the disbelief that such a structure can be supported on a small drum. This is done both internally and externally. Within and without mandalas and arabesques serve to lead the eye up and down in a never ending sequence of patterns that match the flow of prayer and understanding.
The texture and colour of these designs must be such as to suspend the intellectual curiosity and satisfy the longing of the soul. The dome preserves the impression of the heavenly vault while imbuing it with a divine quality. Ardelan and Bakhtiar have summarised the importance of the concept as follows:
Its colours then prototypically become white, green, blue-green, turquoise, gold or a neutral tone of tilework, brickwork, plaster and muted combinations of these. Archetypally, the Dome in all its manifestations is the locus of the Divine Throne, passive to the Intellect, maternal in gender and sublimely timeless in form.