The Hebrew Letter Tet and its mysterious crown.

The 9th Letter of the Hebrew Aleph-Bet is Tet. The letter Tet represents a vessel, a cup or womb and its corresponding number 9 relates to the 9 months of Pregnancy. The 9th month of the Hebrew Calendar is Kislev.

Kislev is a very important month since on the 25th of Kislev Moses completed the Mishkan (Tabernacle) the Temporary dwelling place of the Divine Presence of God on earth. Mi-ShKhN

Tet is also one of the seven letters which receive special crowns (called tagin) when written in a Sefer Torah: Shin, Ayin, Tet, Gimmel, Nun, Zayin, and Tzadi.

The first tet - ט that appears in the Torah is in the word tov of Genesis 1:4, normally translated as good, but a better meaning is beneficial. When it appears in the Torah for the first time, the first letter tet of tov has a very unusual feature. The letter tet, like many other letters in a Torah scroll have tiny crowns extending from them (which kabbalists teach is a hidden language of its own). What is unusual about this letter here is that it has four crowns instead of the usual three. According to the Kabbalist, the B’nei Yissachar, when the four is multiplied by the number nine (the value of the “tet” itself), the total is thirty-six. The word in the Torah used to describe the Hidden or Primordial Light is tov meaning beneficial or good. This demonstrates that the letter nine and the tet - ט represent beneficence. Tov is like the pain of child birth. No one believes that it is good. But everyone believes that it was beneficial because through that pain we receive a New Life. http://www.betemunah.org/nine.html

The Haggadah calls the tagin (crowns) "ḳetarim." "

When Moses ascended to heaven he found the Holy One 'crowning' the letters" (Shab. 89a). In the Midrash, in the comment on Hezekiah's reception of the ambassadors of Merodach-baladan, to whom he showed the "precious things" (Isa. xxxix. 2), R. Johanan says, "He showed them a dagger swallowing a dagger"; and R. Levi adds, "With these we fight our battles and conquer" (Cant. R. iii. 3; comp. Sanh. 104a; Pirḳe R. El. lii., end). Naḥmanides (1194-1270) quotes this midrash with the reading, "Hezekiah showed them the 'Sefer ha-Tagin'" (comment on Gen. i. 1). Maimonides evidently quotes the formula of the tagin for the phylacteries and the mezuzah scrolls from the "Sefer ha-Tagin" (see "Yad," Tefillin, ii. 9; Mezuzah, v. 3); in his responsa "Pe'er ha-Dor" (No. 68, p. 17b, ed. Amsterdam, 1765) he says, "The marking of the tagin in the Sefer Torah is not a later custom, for the tagin are mentioned by the Talmudists as 'the crowns on the letters.' . . . The Torah that Moses wrote also contained tagin."
http://www.jewishencyclopedia.com/articles/14197-tagin
Regarding the crowns (tagin) on the Letter "Tet" I found this very interesting:

The Phoenician letter name ṭēth means "wheel", but the letter possibly continues a Middle Bronze Age glyph named ṭab "good", Tav in Aramaic and Tov טוב‎ in Hebrew, ṭayyib طَيّب in modern Arabic, based on the nfr "good" hieroglyph: Jewish scripture books about the "holy letters" from the 10th century and on discuss the connection or origin of the letter Teth with the word Tov, and the Bible uses the word 'Tov' in alphabetic chapters to depict the letter. https://en.wikipedia.org/wiki/Teth

Writing the Letter: