The Crown retains bonuses from Stones so you can have two effects at the same time. If you bash anyone with the shield they turn ethereal for 15 seconds so they can't hit you nor can you hit them. The staff summons the Dwarven spiders for 60 seconds IIRC.
The staff enables you to summon dwemer centurions even the spiders. The crown grants you the last birthstone effect you had before you changed to your current one. And when you bash with the shield it turns all enemies ethereal, making them unable to attack.
Im not getting an active effect with the crown either
try activating your first stone again i had the same problem it should say x stone activated and y stone activated at the same time when you use the stone
The crown basically looks like a standard silver one with a few extra blue stones placed upon it. And in the dark, the stones have a subtle glow to them. Nothing that would give you away, but you can tell the crown isn't just ordinary too. I really like it.