The symbol of the Sun is on the top of the 8 of Disks, because it is in the sign of Virgo which belongs to the Decan and the number 8 which is Hod (splendor) that represents Mercury. This places Mercury in its highest spiritual aspect. What this signifies is that a loving intelligence applied to material matters. especially those of the Horticulturist, the artificer and the engineer.
The interest of the 8 of Disks, is the interest of the people as applied to labor, agriculture, and creative expression. It is illustrated as the geomantic figure Populus and the disks may represent flowers or fruits of a great tree solidly rooted in fertile land. The essence of Virgo is the secret withdrawing of Energy into the fallow earth. Moreover, Populus is the Moon retiring from manifestation to her conjunction with the Sun. The study of geomantic figures is recommended here. Do a Internet search and you will be directed to the necessary books and information. Blogs leave room for limited comment only.
When the 8 of Disks is thrown during a reading it implies that within 8 weeks or 8 months, or in the past 8 weeks or 8 months, the querent has used, skill, prudence, and cunning in their labor. There is an implication here of being over-careful in small things at the expense of great which could mean gain of money in small sums. Also, industrious cultivation of land is indicated .
If ill dignified. meanness, avarice, hoarding and lack in enterprise are indicated.
However, there is a deeper spiritual meaning as well, for Prudence is part of a Master's Journey, the Swift solar Messenger Mercury, linked with Virgo and the Sun, is again "loving intelligence applied to material matters." . Mastery of Physical, Spiritual, and Mental union is implied here, and as many of us know, the spiritual undercurrent of a Master's journey is in carefully planted steps that often has been referred to as Impeccability... where each moment is to be experienced completely.
Again, the accompanying cards will inform the reader in which direction the 8 of Disks is pointing. There is also an deeply spiritual aspect peculiar to the figure 8; it is O, the symbol of "without end" twisted into what looks to be two separate zeros joined at the cross roads; an intercourse, if you will. This is known as the symbol for Infinity and/or the Magi symbol of the Lemnistrate ( Latin: lemniscus) which is shown as the Figure 8 laying on its side[See the Magus Card Trump #1), To the Tibetan Tantric this is the symbol of Yab Yum which translates to "Goddess God face to face"... What is known to the Magi, is that the figure 8 is how the O-ne became male and female. By one energy twisting upon itself, the concept of male and female---i.e., Goddess/God was created. It could be said that Electric male force and Magnetic Female Force came from God's introspection of "I AM"...which implies existence.
Thank you for your interest and comments. May you live long and prosper.