HPHT Diamond Update
Step 2: Advanced Gemology
|Synthetic Diamond History|
High Pressure High Temperature
Diamonds were first synthesized from graphite in the 1950s by the high pressure high temperature (HPHT) process. In the mid-1980s the process was modified to create diamond film.
Chemical Vapor Disposition
Later chemical vapor disposition (CVD) improved diamond film production.
In the mid-1990s, diamond-like coatings (DLC) improved on CVD, requiring less temperature and less energy.
Cutting tools, optical windows for aerospace, infrared and X-ray instruments, microelectronics, coating for consumer eyewear and bar code readers, wear-resistant coatings for hard disks, read/write heads for videocassette recorders, audio recorders and disk drives.
Semiconductors for high speed computing, ‘cold’ cathodes for flat screen computer and video displays.
In 1999, General Electric introduced a new diamond treatment that can improve the color of some diamonds by several grades. The treatment caused considerable concern. …