It's certainly not pearlberry. I've actually have got the same coral you have pictured. It has taken me well over a year to color it up and it's still not even close to this hyper baby blue color that is pictured.
I think I just found what this is
http://uniquecorals.com/acropora-tenuis-bali-blue-ice-tenuis-2-5-wysiwyg-colony.html">http://uniquecorals.com/acropora-tenuis-bali-blue-ice-tenuis-2-5-wysiwyg-colony.html</a>