As regards the symbol in the Astrological Font, which I finally got around to examining today, it's the old alchemical symbol for Earth. A symbol similar to it is also used to represent the Earth sephira (Malkuth) on the Tree of Life in Qabalah.
Why it was adopted for use as a prop for the Judah Zachary character on DS, I have not a clue.
Perhaps it was meant to be a relic of the Happy Meal of Baal???
There may be different alchemical systems and notations, but I don't think Gerard's is the standard alchemical symbol for earth. Earth, air, fire, and water are all variations on a triangle ... I was involved with something called The Merlin Mystery for a couple of years, which centered on alchemy ... so I became quite familiar with many of the alchemical symbols.
According to the DS FAQ, Gerard's symbol is the Celtic cross. You'd think I would have known that, having been raised Presbyterian ... but truthfully that never rang a bell ...
