Allotropes of carbon dispersion of light of diamond make it useful for both industrial applications and jewelry. Diamond is the hardest known natural mineral. This makes it an excellent abrasive and makes it hold polish and luster extremely well. No known naturally occurring substance can cut (or even scratch) a diamond, except another diamond. The market for industrial-grade diamonds operates much differently from its gem-grade counterpart. Industrial diamonds are valued mostly for their hardness and heat conductivity, making many of the gemological characteristics of diamond, including clarity and color, mostly irrelevant. This helps explain why 80% of mined diamonds (equal to about 100
Substance use disorder Substance use disorder A substance use disorder (SUD), also known as a drug use disorder, is a medical condition in which the use of one or more substances leads to a clinically significant impairment or distress. Substance use disorders are characterized by an array of mental, physical, and behavioral symptoms that may cause problems related to loss of control, strain to one's interpersonal life, hazardous use, tolerance, and withdrawal. Drug classes that are involved in SUD include alcohol, opioids, stimulants, tobacco, hallucinogens, phencyclidine, inhalants, and sedatives. Worldwide 275 million people were estimated to have used an illicit drug in 2016.