The "Creation" spell states:
You pull wisps of Shadow material from the Shadowfell to create a nonliving object of vegetable matter within range - soft goods, rope, wood, or something similar. You can also use this spell to create mineral Objects such as stone, Crystal, or metal. The object created must be no larger than a 5-foot cube, and the object must be of a form and material that you have seen before.
However, nowhere in the description does it add the restriction of nonmagical items.
Almost everything else that creates objects explicitly states that nonmagical items can be created, e.g. Marvelous Pigments:
When you complete the painting, the object or terrain feature depicted becomes a real, nonmagical object.
or Illusory Reality:
you can choose one inanimate, nonmagical object that is part of the illusion and make that object real.
So, due to Creation not specifying this restriction, can I create magical items using it?