Evolution of the Dragon, by G. Elliot Smith, , at sacred-texts.com
During the chequered history of the Great Mother the attributes of the original shell-amulet from which the goddess was sprung were also changing and being elaborated to fit into a more complex scheme. The magical properties of the cowry came to be acquired by other Red Sea shells, such as Pterocera, the pearl oyster, conch shells, and others. Each of these became intimately associated with the moon. 3 The pearls found in the oysters were supposed to be little moons, drops of the moon-substance (or dew) which fell from the sky into the gaping oyster. Hence pearls acquired the reputation of "shining by night," like the moon from which they were believed to have come: and every surrogate of the Great Mother, whether plant, animal, mineral or mythical instrument, came to be endowed with the power of "shining by night". But pearls were also regarded as the quintessence of the shell's life-giving properties, which were considered to be all the more potent because they were sky-given emanations of the moon-goddess herself. Hence pearls acquired the reputation of
being the "givers of life" par excellence, an idea which found literal expression in the ancient Persian word margan (from mar, "giver" and gan, "life"). This word has been borrowed in all the Turanian languages (ranging from Hungary to Kamskatckha), but also in the non-Turanian speech of Western Asia, thence through Greek and Latin (margarita) to European languages. 1 The same life-giving attributes were also acquired by the other pearl-bearing shells; and at some subsequent period, when it was discovered that some of these shells could be used as trumpets, the sound produced was also believed to be life-giving or the voice of the great Giver of Life. The blast of the trumpet was also supposed to be able to animate the deity and restore his consciousness, so that he could attend to the appeals of supplicants. In other words the noise woke up the god from his sleep. Hence the shell-trumpet attained an important significance in early religious ceremonials for the ritual purpose of summoning the deity, especially in Crete and India, and ultimately in widely distant parts of the world. 2 Long before these shells are known to have been used as trumpets, they were employed like the other Red Sea shells as "givers of life" to the dead in Egypt. Their use as trumpets was secondary.
And when it was discovered that purple dye could be obtained from certain of the trumpet-shells, the colouring-matter acquired the same life-giving powers as had already been conferred upon the trumpet and the pearls: thus it became regarded as a divine substance and as the exclusive property of gods and kings.
Long before, the colour red had acquired magic potency as a surrogate of life-giving blood; and this colour-symbolism undoubtedly helped in the development of the similar beliefs concerning purple.
156:3 For the details see Jackson, op. cit., pp. 57-69. Both the shells and the moon were identified with the Great Mother. Hence they were homologized the one with the other.
157:1 Dr. Mingana has given me the following note: "It is very probable that the Græco-Latin margarita, the Aramæo-Syriac margarita, the Arabic margan, and the Turanian margan are derived from the Persian mar-gân, meaning both 'pearl' and 'life,' or etymologically 'giver, owner, or possessor, of life'. The word gān, in Zend yān, is thoroughly Persian and is undoubtedly the original form of this expression."
157:2 See Chapter II of Jackson's book, op. cit.