If you pour paraffin wax too cold the surface of the candle will be rough in texture. If you try to pour paraffin too cold to reduce shrinking it can result in what are called “jump lines” that look like rings especially using containers. Paraffin wax should be poured hot at 175-185 degrees Fahrenheit.
If you are looking for a rustic look, pour paraffin at about 160 degrees or use palm wax. Never pour paraffin below 160 degrees Fahrenheit.
If you pour paraffin wax too cold in an environment the wax will set too quickly and may crack. The surface may have lines from cooling rapidly. Also, avoid drafts.