synthetic has different meanings to people. We may be thinking "man made molecules" but they are all derived from other materials, mineral, vegetable, hydrocarbon, etc. So much of what is 'synthetic" oil is petroleum based from oil, and then extremely modified by distilling, filtering, heating, recombining etc. But still based from oil. And then there are type 4 (I think) synthetic oils derived from natural gas. But most of it all just starts out as oil. Even petroleum distillates are found in some white vinegar, or baby oil/min. eral oil, or petroleum jelly that we stick on out bodies is derived from petroleum oil. A little off topic, sorry. Now the next technology is nano-lubricant particles, which are extremely small, and may have a downside effect of being able to readily move into our skin, water and environment.