Always clean skin meticulously, an acne skin is very sensitive. Eat a well balanced diet, avoid fatty food and take plenty of exercise, especially in the out-of-doors. Certain pure essential oil can be applied neat to individual marks-such as: 1  Tea tree oil. 2  Lavender oil.
The grain is a measure of weight. 1 grain is equal to 1/7000th of a pound. Or 7000 grains are in 1 pound. There are 15.43 grains per gram for those who are metric. It's just a weird way of saying how heavy something is in firearms. More grains means heavier bullet.
Particle size, also called grain size, refers to the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. This is different from the crystallite size, which refers to the size of a single crystal inside a particle or grain. A single grain can be composed of several crystals. Granular material can range from very small colloidal particles, through clay, silt, sand, and gravel, to boulders.