It is genetic - in my family there is no history of it as it is a recessive gene but my mum and dad were both carriers. In Scotland up to 13% of the population has red hair, but around 40% of the population is thought to carry the recessive gene responsible for the world's rarest natural hair colour.
On the other hand, synthetic base oil molecules are chemically controlled, which provides increased ï¬ lm strength and lubricity over petroleum oils. The performance qualities of base oils have a marked impact on the performance qualities of the ï¬ nished product.
There are three main three main categories of consumer motor oil. There are conventional petroleum-based oils, and there are synthetic versions created from chemicals. A third category includes products called part synthetic, which combine conventional mineral oil with man-made chemicals. Conventional motor oil is based on crude oil that goes through extensive refining to make it suitable for engine use. Synthetic oil, however, is created through chemical reactions. And like so many other technological advances, synthetics were born in a time of conflict.