This is an excerpt on my longer blog post about the Tower card:
The pendant design closely mimics the card’s illustration. Lightning strikes a tower, setting it aflame and causing the crown to fall to the side.
The reverse of the Tower pendant with sigil
The reverse of the pendant is comprised of a Martian glyph striking downwards through the top square stacked on another square. The two squares signify generations, or build up of structures & systems. The Tower card corresponds to the planet Mars and so the glyph of Mars is the active force, or the lightning. Atop the tower is the crown of three upright triangles, signifying elemental fire and the heat & friction of transmutation.
A final note: Why would anyone want to wear the Tower as an energy around their neck, so to speak? Well, becoming the force of change in your own life & embodying Martial energy for action and transformation can be a way of overcoming feelings of helplessness. Perhaps the Tower will remind you of your ability to hold fast but also to crumble and begin again with grace when it is necessary.