Stands for "High Pressure High Temperature." It is a process that is used to create lab-grown diamonds. Lab-grown diamonds are diamonds that are created in a laboratory setting, rather than being mined from the earth. The HPHT process involves recreating the
high pressure and high temperature conditions that exist deep within the earth, where natural diamonds form. In this process, a small diamond seed is placed in a metal container and subjected to extremely high pressure and temperature. As the conditions within
the container are carefully controlled, the seed begins to grow, forming a larger diamond crystal. The resulting lab-grown diamond is chemically, physically, and optically identical to a natural diamond, but it can be produced much more quickly and at a lower
cost than mining a diamond from the earth.