Characterization of type Ib CVD synthetic diamonds and estimation of their annealing temperature after the growth.

Abstract

We tested fifteen pieces of type Ib yellow CVD synthetic diamonds which were submitted to the Central Gem laboratory without disclosure. From FTIR analysis, together with optic centers detected by photoluminescence (PL) analysis such as H3, NV or N3 centres, indicate that those stones have undergone post-grown HPHT treatment at about 1900-2200 degree of temperature.