Q. My Honey has become solid. Is it pure?
This is unfortunately a widespread misconception going around. Honey crystallization is a natural process which occurs when the naturally present glucose in honey precipitates out of the liquid honey. It does not in any way indicate impurity of honey.

To reverse crystallization and liquefy honey, simply place bottle in hot water and stir to dissolve crystals.
Q. Why is honey heated?
Honey is gently heated to remove any sugar tolerant yeast. It is also needed for filtration and production purposes. This gentle heating does not cause any nutritional changes in the honey.