Black Pearl...... you ever see the standard Pro-Tec color called Smoke? Click the link below and go to color #63. It is a black color with a silver metallic finish - sorta. If i was to guess, they take plain black and mix it with mica powder or something very similar. It may be what you are looking for and you could always add a tap of silver holo glitter over top if you want a little more sparkle. Then a tap of black flake to really give a good BLACK contrast...... ok, i went too far didn't i?
I do have heads painted that exact way though.
http://www.csipaint.com/products/powder-coatings/pro-tec-powder-paint.php
The mica powder is about as finely ground of a 'glittery' material i have seen. It thoroughly mixes with the powder color and changes the appearance of the color. I have a bunch of colors of straight glitter from Junk-Mart and they work good, i have the smaller of the 2 sizes they have on the shelf - kids craft isle. The glitter that is mixed in with the Pro-Tec brand is maybe just a hair smaller than the craft stuff i have. They all work!
I started out cutting back the cure temp and increasing the time (as recommended by the company) but now i just cure all my glittery heads the same as non-glitter - as recommended by Radtex here on the forum.
Never had a problem with the glitter melting or anything else............. yet.