On the exterior, the mandala of Manjushri is depicted which is made of sterling silver with central ruby and lapis lazuli flower. The mandala has four gateways in cardinal directions which are filled with Sterling Silver jewels. A mandala is a sacred diagram of the universe, and encompasses an area in which divine forces are present. A mandala also aids the devotees in meditation when he or she seeks to focus on divinities and to gain access to divine forces. Faceted fifty beads of ruby surround the scene. At the top there is a tube with faceted twin ruby and an emerald and at the bottom, are twin ruby and reel ornamental tube appears capped with conical ends, and below that is a ring with an emerald for suspending other ornaments or tassel. The outer side wall of the Box is decorated coral flowers. The cover of the Gau Box opens with a hinge at the top to reveal the image of Manjushri the Bodhisattva of wisdom. His image is made of turquoise beads. He sits in vajraparyankasana on an exquisitely decorated sterling silver throne with an emerald at front, against a turquoise aureole with filigree work. His right hand holds a flaming wisdom sword while left hand, a lotus flower. He is adorned with a gold plated crown, necklace and other ornaments with ruby and coral.
Manjushri is, in essence, the patron of Nepal, since he is considered to have cut the Valley and drained the great lake for the benefit of humanity. He is worshipped both in gratitude and as the patron of learning and wisdom. Manjushri, which means "Beautiful Glory", can also be translated as "Beautiful Goddess", interestingly in Nepal, he is conflated with the goddess Saraswati, the Hindu goddess of knowledge, and both deities can be worshipped at his shrine on the western spur of the Gosringu Parbat, the hill on which Svayambhu Mahachaitya is located.
Manjushri is considered as the first Bodhisattva in Buddhist Pantheon and his cult apart from Nepal is very popular in Tibet, Mongolia, China, and Japan and in many other Buddhist countries including India.
This description is by Dr. Shailendra K. Verma, whose Doctorate thesis is on "Emergence and Evolution of the Buddha Image (From its inception to 8th century A.D.)"