Theoretically.
But that kind of thing gives the DM headaches.
In the case of a Shades (Wall of Iron), the lack of a material component doesn't hurt anything (but the fact that the instantaneous and thus *non-magical* wall you just created permits a will save to disbelieve and Spell Resistance to ignore, gives headaches).
When you get to spells with "active" components (that is, components actively described as being used for something; (the doll for Contingency (accessible by way of Greater Shadow Evocation) is listed as being required on the caster's person for the contingency to take effect, the gem for Instant Summons must be crushed to complete the spell and call the item, the gem for Trap the Soul actually contains the creature, and so on) the DM has a call to make: RAW, there's no need for the foucs/component. So what happens? Spell can fail, spell can fake up the component, whatever - but it's the DM you need to ask.