A key characteristic of Petrarchan sonnets is the blason, which can be either elaborate praise for the subject or excessive blame or scorn. In most cases, it is the former. The poem achieves the blason detail by detail. For example, it would not be enough for the narrator to express his love or to say that the woman in the sonnet was beautiful. Instead, her beauty would be presented in detail, such as the brightness of her eyes, the smoothness of her skin and the fullness of her hair. In describing the subject's beauty or the narrator's feelings, Petrarchan sonnets make extended use of metaphor and simile. For example, in Petrarch's Poem 292, he says that Laura's smile would "make a paradise on earth" and he calls her "the light I loved so much." Metaphor is also used to describe how he feels after her passing, as "In a great storm on an unprotected raft." Metaphor and simile are heavily used in the blason, but they can be used anywhere throughout the sonnet.
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