Pink Around Tourmaline Growth Tubes Results from Natural Irradiation

A year long examination of blue to blue-green, copper-bearing tourmaline containing surface-reaching growth tubes surrounded by intense pink “sleeves” have been found to be naturally occurring the GIA said Wednesday in a trade alert.

In response to rumors of possible diffusion treatment, GIA Laboratory staff members John I. Koivula, Kevin Nagle, Andy Shen and Philip Owens examined several of these tourmalines over the past year. Based on this examination, the GIA team determined that the pink zones were produced by fluids containing naturally occurring radioactive material.

“Since radiation is the cause of pink color in tourmaline, the presence of these features should not be attributed to any type of intentional diffusion, but rather to the influx of radioactive fluids in their post-growth environment,” said GIA Laboratory Chief Gemologist Koivula.