Schematic of a belt press Inside the HPHT system, there are actually three primary push models applied to supply the stress and temperature needed to deliver artificial diamond: the belt press, the cubic press and also the split-sphere (BARS) press. Diamond seeds are placed at the bottom from the push. https://dominickqiarh.thezenweb.com/lab-grown-diamond-enegagment-ring-no-further-a-mystery-64878342