✵The TCM herbalism is also known as pharmaceutics of Traditional Chinese Medicine, or Chinese pharmaceutics, is the branch of health science dealing with the preparation, dispensing, and proper utilization of Chinese herbs. It is majorly composed of Introduction of Chinese Medicinals, Classification of Chinese Herbs, Formulas, and Patent medicines.
Classifications of Herbs:Herbs for External Use.
Introduction: Herbs for External Use: an agent or substance herbs that used externally for external disease.
✵Till the date March 19th, 2020, there are totally  kinds of common TCM herbs,  kinds of related plant species,  kinds of related insect species,  kind of minerals, are recorded in this category. These herbs for external Use are briefly introduced separately:
Brief Introduction: The herb Realgar is a mineral, orange to reddish, mainly composed of arsenic disulfide(As2S2), used externally as a detoxicant and antiparasitic agent for snake and insect bites, boils and scabies. The herb is commonly known as Realgar, Xiónɡ Huánɡ.
✵Common official herbal classics and other famous herbal classics defined the herb as Realgar as the mineral mainly composed of arsenic disulfide(As2S2), it is a mineral belongs to the realgar group in sulfide minerals. This commonly used mineral is introduced as:
Natural Realgar: Monoclinic system. The crystals are columnar, with vertical stripes on the crystal surface, and most of them are dense blocky or granular aggregates. Color is orange-red, a few are dark red. Streaks pale orange. Crystal surface with diamond luster, the cross-section with resin luster. Translucent. Cleavage is more complete. The fracture is shell-like. Hardness is 1.5~2.0. Specific gravity is 3.4~3.6. Crispy. By the effect of light, long into talk about orange powder. Occurs in low-temperature hydrothermal veins, also occurs at hot springs and nearby volcanoes. It is often associated with realgar and stibnite.
Natural Environment: It is mainly produced in the middle reaches area of the Yangtze River, southwest area, and other areas of China.
Trait identification: Irregular canyons of various sizes. All are dark red or orange-red, often covered with orange powder. Weight, quality is loose fragile, the section is coarse, red, bright. It has a peculiar odor. One of the bright colors, translucent, shiny people used to say "Ming Xiong", "Xiong jing" or "waist yellow". Red color, block, loose quality, no stone is better. It is insoluble in water and hydrochloric acid, it is soluble in nitric acid and yellow in solution; It is brown in a solution of sodium hydroxide. Burning easy to melt into the red-purple liquid, and produce yellow-white smoke, a strong garlic odor; After cooling, the molten matter condenses into a reddish-purple solid, while the pure matter condenses into an orange solid.
Red or orange. The chemical composition is mainly arsenic sulfide AsS, with a small amount of other heavy metal salts.