Over time, many types of honey will granulate, or crystallize. This is a natural process that can occur. The honey looks cloudy, and results in a separation with a liquid part on the top and a more solid, crystallized part on the bottom. Depending upon the original nectar source, this granulation or crystallization rate might differ from honey type to honey type, but it’s a normal occurrence, and not harmful in the least.
Granulated (or crystallized) honey is just as safe to eat as non-granulated honey, but it can be easily restored to its natural state. Just warm up the container with the granulated honey in hot water. The crystals will melt and the honey will re-liquefy easily, although each time it’s re-heated, the honey will granulate slightly quicker than before.