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Kether, however, is specifically associated with the Primum Mobile, not the sun, which is associated with the sixth Sephiroth, Tiphereth, the beauty and splendor of god, as WBY mentions on page 282 below and as Macgregor Mathers lists them in his preface to The Kabbalah Unveiled London: G.
Earth, after being overwhelmed by the waters, rising again, glorified and crowned with the triple crown of silver, iron, and gold — Chesed, Geburah, and Tiphereth, in the alchemic Sephiroth of the metals.
Chesed, and Geburah, thrice; Tiphereth, six times; Netzach and Hod each four times; and Yesod twice.
Tiphereth, and Microprosopus the Son united to D = 4, the Cross.