One pretty interesting theory I came across a long time ago is that, essentially, crystalized structures of matter (muddy river banks, inside caves, etc.) began competing for dominance incidentally as a consiquence of the fact that some crystalline structures propagate themselves more, or less, efficiently depending on the initial properties of their lattices and geometric arrangements.
Over time natural selection took hold and the world may have become dominated by a specific type if crystal structure that could propagate itself with greater efficacy than the rest.
Over time, vast beyond anything compatible to modern life, these structures began to accumulate greater degrees of complexity and ability to utilize more complex or archaic forms of matter for the reproduction of the geometric patterns inherent to the "organism".
Seems like it has a sporting chance of being about right.