The Shroud of Silk
Basic Items are just things someone might find out in Shadow. They can be of high quality, useful, even highly technological or magical, all for no points at all. Basic items rarely have any special properties outside the Shadow they were found in, and can be much more easily destroyed than an actual item of power. Basic Items are never made of Substance, they are always Shadow.
Items of Power
Items of Power are often, but not always items of Substance. Some may simply be very powerful expressions of Shadow that appear when bidden by a person of Substance, i.e. the character who purchased the item. In this way these items are part of the personal legend of the character, more created by them than found. This allows the item to be found again in Shadow no matter how lost it might have become.
Tier 1: At this level of item, the object might merely be of Substance, or it might be a Shadow item with some interesting abilities. Tier 1 items have more low-key abilities, an alternate form and a minor power, or something more powerful but draining to the user.