April 13, 2006
Nichiren's Sig & Seal
Rev. Ryuei wrote: "Nichiren's kao (signature) below the Odaimoku on the Omandalas may either be a highly stylized form of Myo or it may be the Sanskrit letter that represents "Great Sun." Apparently there are different opinions about this in scholarly circles."
On this early mandala, to your right, the signature and seal are on opposite sides. His signature is two Kanji for Nichi & Ren. Kao is maybe best translated as seal. On many mandalas, Nichiren's seal is drawn on top of the 'sig'.
In GohonzonForum@yahoogroups.com, mark wrote:
."... i remember that Rev. Kubota of Hos-shoji temple in Japan stated that Nichiren's personal ka-o (elaborate priestly official signature) embodies the Siddham Sanskrit syllable "VAM", which is a seed sound representing Mahavairocana..."
Actually, I do not think "VAM" is the correct name. There are 6 seed syllables for Birushana aka Dainichi Nyorai {Skt. Vairocana or Mahavairocana Tathagata}. These can be viewed here: DAINICHI NYORAI Nichiren drew two of these on his Esoteric Ichinen Sanzen Mandala.
The locations of the signature & seal vary widely on the extant mandalas. On some, the seal is drawn over his signature and centered below the Daimoku. On others, they are off to the side. Sometimes, they are separate. Here is a pic of Nichiren's seal drawn over his signature.
Below are pix of his seal {kao} and signature drawn separately. 
*****************************************************************
For discussions of the Nichiren Gohonzon:
GohonzonForum · Gohonzon Forum
Description
This is an open discussion about the Gohonzon, the Great Mandala of the Lotus Sutra. Most groups have a prefered Gohonzon; for some any valid Gohonzon is acceptable. Currently Nichiren Shoshu prefers the Nikken, the SGI encourages the Nichikan but discourages the Nikken or any Nichiren Gohonzon except the DaiGohonzon of Taisekiji. The Independent Movement uses a Nichiren Gohonzon called the Prayer Gohonzon.
This site is intended for open discussion by members from all Nichiren traditions. This includes theology and theory, info on how to receive different Gohonzons and experiences related to Gohonzon acceptance or transfers. Discussion is welcome of personal perceptions of the dynamics of Nichiren practice, of which the Gohonzon is central. Debate is acceptable as long as it is conducted with courtesy and respect for the person and beliefs of others. Disrespect, flaming and spamming are not permitted. Personal insults and accusations are also not permitted. Accusation of slander are not permitted. Defending the honor of your viewpoint with anything except compassion and respect to all beings is not permitted.
******************************************************************