Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Mineral
D010578
Petroleum
Naturally occurring complex liquid hydrocarbons which, after distillation, yield combustible fuels, petrochemicals, and lubricants.
State bounded on the north by Wyoming and Nebraska, on the east by Kansas and Nebraska, on the south by New Mexico and Oklahoma, and on the west by Utah.
D006801
Humans
Members of the species Homo sapiens.
Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012871
Skin Diseases
Diseases involving the DERMIS or EPIDERMIS.
Dermatoses,Skin and Subcutaneous Tissue Disorders,Dermatosis,Skin Disease