Does all spells that create "magical darkness" create shadowy illumination as described in the spell Darkness.

For example Black Sand (Sandstorm, pp112)

This spell creates an area of black sand (see page 20), infused with shadowstuff and negative energy. A region of black sand literally swallows light, emitting magical darkness rising to a height of 20 feet over the surface

Does all spells that create "magical darkness" create shadowy illumination as described in the spell Darkness.

For example Black Sand (Sandstorm, pg. 112)

This spell creates an area of black sand (see page 20), infused with shadowstuff and negative energy. A region of black sand literally swallows light, emitting magical darkness rising to a height of 20 feet over the surface

As per the title, is it shadowy illumination or total darkness? Or something else?

Does all spells that create "magical darkness" create shadowy illumination as described in the spell Darkness.

For example Black Sand (Sandstorm, pp112)

This spell creates an area of black sand (see page 20), infused with shadowstuff and negative energy. A region of black sand literally swallows light, emitting magical darkness rising to a height of 20 feet over the surface