Mineral engine oil is where motoring lubricant started (in monograde form) and is very popular. It can still offer extremely high quality, but can also suffer from a lack of advanced blending and quality base stocks. We sell mineral oils at the quality end of the spectrum, but even so, these days mineral oils is generally recommended for the more basic engines.
Mineral oil is a liquid petrolatum, making it an ideal choice for a number of applications. It's one of a number of inexpensive by-products that are made from petroleum, and is less expensive than synthetic oils due to the easier production and blending process.