Origin
It is believed that the name “BiaGae”, was derived from the words “Bia” and “GaeBon”. Bia refers to a shell, and GaeBon describes a process where one gives offerings in appreciation for wishes granted by deities and Sing Saksit. Thais would string flowers into garlands to hang around the statue.
There is much symbolism associated with the conch shell, particularly with the creation of the universe. The sound made by blowing through the conch shell is symbolic of the “Om” sound, which heralded the beginning of existence itself.
Legend has it that when the new universe was created, and life began to flourish on Earth, a demon named SangAhSoon
Phra Wisanu (Vishnu in Hindusim) was alerted to this treachery by Phra Phrom (Brahma, the Creator). He transformed himself into a fish, preparing to battle the demon and retrieve the scriptures, which contained the secrets of life. Dispatching the demon in combat, Phra Wisanu ripped the scriptures from SangAhSoon’s stomach and claimed the conch shell for himself.
As a result of this close association, Phra Wisanu is invoked whenever conch shells are used for ceremonies. Phra Wisanu, is associated with the preservation of life, as well as the triumph of good over evil. There are many transformations of Phra Wisanu, and Phra Narai (Narayana) is one of them. In Brahmanism, Nara means “water”. It has reference to the waters of creation, mostly referring to human beings. Ayana means “resting place”. Thus the name Narayana roughly translates as “a refuge for human beings”.
The legends also say that it was Matsya

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The spiralling dome of the conch shell is symbolic of infinite space. It is also symbolic of the feminine life force (Shakti); the shell’s spiral form and relation to water are representative of the beginning of existence (birth), which is presided over by Goddesses such Phra Mae Uma, Phra Mae Laksami and Phra Mae Srasawadee. This is why all seashells are considered sacred.

History
Bia, are cowry shells, brought to the kingdom of Siam by Persians and Arabs in ages past. They travelled to East Siam via the sea. The cowry shells were acquired in the Maldives and Philippines. They are beautiful and hard, and difficult to find in Thailand. The Thais used them to make ornaments, and also as a primitive form of currency. A Silajareuk (stele) dating to the Sukhothai

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Until the period of King Rama IV, it was popular to embed precious gems in cowry shells, and wear them as a display wealth. The King was worried that this might lead to an increase in robberies and looting, and issued a decree barring commoners from wearing such jewellery. These bejewelled BiaGae were called PakaWahJan

These were made from the shells of Hoi Taley Gup Deow

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How to make BiaGae
A cowry shell with 32 “teeth” must be selected; 16 on the right, 16 on the left. Mercury is placed into the shell, and the shell is covered with chanloong (a paste derived from the hives of Apidae Trigona Apicalis, a type of stingless bee). The shell is then covered with lead, and inscribed with yant. The shells are then wrapped in string, and sealed with longrak, a type of smooth, shiny lacquer.

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The craftsman will then pluksek