Rare stamps are gold. They do not have colors or themes for scoring purposes. Since they are especially valuable, they may not be reserved during the Swap Phase.
Canceled stamps have a wavy mark in their top-right corner. They have colors and themes, but they do not have a value.
Faded, lower grade stamps have negative values. They have colors and themes, but they decrease your album’s value.
Forever stamps are the smallest. They have no colors, themes, or values.