NOt so sure, but found:
What's a mandala ?
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Mandala comes from the Sanskrit word which means circle. Sacred work, the mandala thrusts its roots deep into the religions like Tantrism and Buddhism. Some wonderful examples can be notably seen in Tibet.
At first sight, the mandala, which represents the cosmos, is a kaleidoscope of geometric designs executed in vivid colors. A closer look reveals a multilayered world of meaning.
For instance, the basic shape of a mandala is a square, representing palacewalls with four gates corresponding with the compass points. In the center is a circle in which the sacred figure (or figures) that are the subject of the painting may be depicted.
The center is often blue, a color signifying ignorance, a quality which when transcended becomes wisdom. The four quadrants of the square also have special meanings.
In many mandalas, east is white, which means anger or, transcended, insight; south is yellow, which means pride or, transcended, equanimity; west is red, which means greed or, transcended, compassion; north is green, which means jealousy or, transcended, achievement. Circles of lotus leaves surrounding the center and the square signify purity, as does an outer rim of five-flamed fire. The mandalas, which originally often were painted as murals, are mainly used as a means to meditation.
http://www.artistenomade.com/gb/art_asie.htm
first, in front of the Buddha's image, use some clean soil to construct a square mandala, the size according to one's wish. On top of the mandala one should spread different kinds of grass, flowers and burn different kinds of quality incense. Then kneeling down with the right knee on the floor, mindfully reciting the Buddha's name and with the hands in the Mudrani symbol, (i.e. each hand bending the forefinger and pressing it down with the thumb and placing both palms together before the chest) in reverence, one should recite this Dharani 108 times. The showers of flowers would rain down from the clouds and would thus be universally made as offerings to Buddhas as numerous as the grains of sand of eighty-eight million Ganges Rivers. These Buddhas will simultaneously praise, "Excellent! Rare indeed! A Buddha's true disciple!" One will instantly attain Unobstructed Wisdom Samadhi and the Great Bodhi Mind Adorned Samadhi. Thus is the way to uphold this Dharani."
http://www.geocities.com/usnisa_vijaya/web/eng/content/37.htm