Consider the lines: 'The sun is a golden coin / Tossed by the gods across the sky.' These lines are an example of

An extended metaphor develops a comparison across more than one line or image. Here, the sun is compared to a golden coin, and the comparison is extended further by the idea of it being 'tossed by the gods.' The metaphor is sustained beyond a single phrase, making it extended. Personification would require the sun to be given human traits, which is not the primary device here.