Do the lab grown diamonds come out of the process as the cubish shape as rough diamonds? Do you still send them off to be cut/polished by 3rd parties? How do you sell them?
HPHT (high pressure, high temperature) grows from a tiny diamond seed (<1mm) and the growth sort of "snowballs". Blue and white/colorless are a hexacubic type shape while yellow are a truncated octahedron shape.
White/Colorless: http://d.neadiamonds.com/images/rough-hpht-white.jpg Yellow (industrial recipe): http://d.neadiamonds.com/images/rough-hpht-yellow.jpg
CVD (chemical vapor deposition) grows basically straight up from a diamond plate, so are generally cuboids. Spontaneous polycrystalline diamond can grow on the sides, but is hard, black and unusable for the same applications as single-crystal. CVD (poly is cut off): http://d.neadiamonds.com/images/rough-cvd-brown.jpg
When CVD grows brown or gray, it is usually due to atomic-level defects in the diamond, which can be healed through post-growth treatment, turning it a near colorless or light yellow color. This CVD photo was HPHT treated to a light yellow, then further treated to become a nice fancy pink. It is also possible to have CVD grow near colorless, without requiring treatment.
We sell diamonds for jewelry on our retail website: https://d.neadiamonds.com They are also available for high-value industrial and wholesale jewelry applications.