I suppose that I intrinsically knew that olive oil could solidify, as all fats do at some temperature, but it took one of my grocery-retrieving children leaving a bottle of the stuff in the car for a few days for me to personally experience solidified olive oil. In the picture on the left, the solid olive oil is the whitish lump in the lower right hand portion of the bottle.
I learned today that olive oil begins to solidify at about 43 degree Fahrenheit, which is about 6 degrees Celsius for those of you who live in nations that have embraced the rationality of metric units of measure.
I also learned that there is no harm in consuming olive oil that has solidified, and room temperatures will return the oil to a liquid state. I read that the return to liquidity might make the oil a bit cloudy, but this will only be problematic for those who are as particular about their cooking oils as they are about their wines. Some experts, in fact, advocate refrigerating oilve oil and bringing out only the amount you want to use each day, and they argue that this will reduce the likelihood that your olive oil will turn rancid in warm temperatures or impoperly sealed containers.